Indexes performing poorly on $in

“Based on the shared image, it appears that the query execution time is around 378 ms. Please let me know if I’m missing something.” - If I run db.someCollection.find({someId :{$in: [ <260 objectIds> ] }}).sort({_id:-1}).explain(“executionStats”) it shows 378 ms, but if run db.someCollection.find({someId :{$in: [ <260 objectIds> ] }}).sort({_id:-1}) it sometimes doesn’t even returns a result, if I check the profiler the docs returned are shown as null and time taken is around 15 min or so. Majority of cases nothing is returned further hampering our prod env.

Requested sample docs:
(Please note that some docs contain images and the size of an image is around 3.6MB each. There around 6 images , and also the signatures are encoded. Due to images in documents the size of doc is 15MB for around 9022 documents in the collection, otherwise the docs without the images have size around 90KB )

1. {
    "_id": "61ffffffffffffffffffffff",
    "isSomesome": false,
    "issometed": false,
    "someeeeeeeeBy": "Ksome Rrrr",
    "isSomeeee": true,
    "isSssssssssst": false,
    "dummyyyyId": "600000000000000000000000",
    "someeeId": "5ddddddddddddddddddddddd",
    "someId": "5drrrrrrrrrrrrrrrrrrrrrr",
    "asssssssssnkId": "5ffffffffffffffffffffff",
    "nameOfSigner": "Ksome Rrrr",
    "signerRole": "",
    "userAgent": "Hhhhhhhhh/3 CFfffffff/1111.0.1 Ssssin/22.6.0",
  "ipAddress": "111.111.11.111",
  "somedddId": "6555555555555555556666",
    "created": "2022-02-04T19:51:47.000Z",
    "updated": "2022-02-04T19:52:03.712Z",
    "noteAssessment": {
      "notes": "Forms",
      "isClearanceNote": false,
      "isPhysicalNote": false,
      "images": [],// 6 images size 3.6MB
      "date": "2022-02-04T19:49:00.000Z",
      "isNeuropsychNote": false,
      "injuryType": "",
      "attachments": [
        "613333333333333333333333/attachment_0.png",
        "61tttttttttttttttttttttt/attachment_1.png",
        "61fdyyyyyy55555555555555/attachment_2.png",
        "61fdwwwwwwwwwwww33333333/attachment_3.png",
        "61f666666666666666666666/attachment_4.png"
      ]
    }
  }

2. 
{
  "_id": "xx",
  "isDummyyy": false,
  "someeeeeeeeBy": "Ttt Ccccccc",
  "isSomeeee": false,
  "dummyyyyId": "666666666666666666666666", //Objectid
  "someeeId": "62222222222222222222222",//Objectid
  "someId": "61111111111111111111111",//Objectid
  "someeeeSignature": "encoded",
  "nameOfSigner": "Ttt Ccccccc",
  "signerRole": "Hhhh Ttttttttt/Ttttttt",
  "someeeeeeeType": "sssssSsssssss",
  "someersion": "7.2.0",
  "userAgent": "Hhhhhhhhh/3 CFfffffff/1111.0.1 Ssssin/22.6.0",
  "ipAddress": "111.111.11.111",
  "somedddId": "64444444444666666666666", //objectId
  "created": "2023-08-18T16:56:36.030Z",
  "updated": "2023-08-18T17:06:43.524Z",
  "basomeeYest": {
    "sinssssssssssssFfffDssssse": 1,
    "doSSSSSeeeeeeeeeeeeeeeeeeeee": 1,
    "tasomeStsomeOnFirmSurface": 1,
    "wasPerformed": true,
    "nonDominantFoot": "left",
    "testingSurface": "hardFloor",
    "footwear": "shoes"
  },
  "cognitiveAssessment": {
    "whatMonth": true,
    "whatDate": true,
    "whatDay": true,
    "whatYear": true,
    "whatTime": true,
    "trialFirst": 10,
    "trialSecond": 10,
    "trialThird": 10,
    "numbersFirst": true,
    "numbersSecond": true,
    "numbersThird": true,
    "numbersFourth": true,
    "valueMemoryReverseMonthTime": 7.292173981666565,
    "valueMemorySecondFirst": 1,
    "valueMemorySecondSecond": 1,
    "valueMemorySecondThird": 1,
    "valueMemorySecondFourth": 1,
    "valueMemorySecondFive": 1,
    "valueMemorySecondSix": 1,
    "valueMemorySecondSeven": 1,
    "valueMemorySecondEight": 1,
    "valueMemorySecondNine": 1,
    "valueMemorySecondTen": 1,
    "digits": "4-9-3 6-2-9, 3-8-1-4 3-2-7-9, 6-2-9-7-1 1-5-2-8-6, 7-1-8-4-6-2 5-3-9-1-4-8",
    "wordNames": "Baby, Monkey, Perfume, Sunset, Iron, Elbow, Apple, Carpet, Saddle, Bubble",
    "firstTrialSelectedValues": "1,1,1,1,1,1,1,1,1,1",
    "secondTrialSelectedValues": "1,1,1,1,1,1,1,1,1,1",
    "thirdTrialSelectedValues": "1,1,1,1,1,1,1,1,1,1",
    "immediateMemoryCompletedTime": "2023-08-18T16:58:25.189Z",
    "delayedRecallStartedTime": "2023-08-18T17:06:29.344Z",
    "wasPerformed": true,
    "immediateMemoryTrialsAudio": [
      "trialFirst",
      "trialThird"
    ],
    "digitsAudio": [
      "4-9-3 6-2-9",
      "3-8-1-4 3-2-7-9",
      "6-2-9-7-1 1-5-2-8-6",
      "7-1-8-4-6-2 5-3-9-1-4-8"
    ],
    "language": "eng",
    "valueReverseMonthsCorrect": ""
  },
  "symptomEvaluation": {
    "headache": 0,
    "pressureInHead": 0,
    "neckPain": 0,
    "nauseaOrVomiting": 0,
    "dizziness": 0,
    "blurredVision": 0,
    "balanceProblems": 0,
    "sensivityToLight": 0,
    "sensivityToNoice": 0,
    "feelingSlowedDown": 0,
    "feelingLikeInAFog": 0,
    "dontFeelRight": 0,
    "difficultyConcentraiting": 0,
    "difficultyRemembering": 0,
    "fatigueOrLowEnergy": 0,
    "confusion": 0,
    "drawsiness": 0,
    "moreEmotional": 0,
    "irritability": 1,
    "sadness": 0,
    "nervousOrAnxious": 0,
    "worseActivity": 0,
    "worseMentalActivity": 0,
    "feelingNotNormal": 97,
    "wasPerformed": true,
    "assssssSignature": "encoded",
    "language": "english"
  },
  "someIId": "64dddddddddddddddddddddd", //objectid
  "tandemGait": {
    "trial1": 6.467267036437988,
    "trial2": 6.117172002792358,
    "trial3": 6.384270071983337,
    "wasPerformed": true,
    "ableToPerformTandemGait": true,
    "ableToPerformTandemGaitNotes": "Sprained ankle "
  },
  "dualTaskGait": {
    "firstTrialTime": 23.499022006988525,
    "practiceTrialValues": [
      {
        "expectedAnswer": 93,
        "givenAnswer": 93
      },
      {
        "expectedAnswer": 86,
        "givenAnswer": 86
      },
      {
        "expectedAnswer": 79,
        "givenAnswer": 79
      },
      {
        "expectedAnswer": 72,
        "givenAnswer": 72
      },
      {
        "expectedAnswer": 65,
        "givenAnswer": 65
      },
      {
        "expectedAnswer": 58,
        "givenAnswer": 58
      },
      {
        "expectedAnswer": 51,
        "givenAnswer": 51
      },
      {
        "expectedAnswer": 44,
        "givenAnswer": 44
      },
      {
        "expectedAnswer": 37
      }
    ],
    "secondTrialValues": [
      {
        "expectedAnswer": 90,
        "givenAnswer": 83
      },
      {
        "expectedAnswer": 76,
        "givenAnswer": 76
      },
      {
        "expectedAnswer": 69,
        "givenAnswer": 69
      },
      {
        "expectedAnswer": 62,
        "givenAnswer": 62
      },
      {
        "expectedAnswer": 55,
        "givenAnswer": 55
      },
      {
        "expectedAnswer": 48,
        "givenAnswer": 48
      },
      {
        "expectedAnswer": 41,
        "givenAnswer": 41
      },
      {
        "expectedAnswer": 34
      }
    ],
    "wasPerformed": true,
    "secondTrialStartingValue": 90,
    "thirdTrialValues": [
      {
        "expectedAnswer": 98,
        "givenAnswer": 98
      },
      {
        "expectedAnswer": 91,
        "givenAnswer": 92
      },
      {
        "expectedAnswer": 85,
        "givenAnswer": 85
      },
      {
        "expectedAnswer": 78,
        "givenAnswer": 78
      },
      {
        "expectedAnswer": 71,
        "givenAnswer": 71
      },
      {
        "expectedAnswer": 64,
        "givenAnswer": 64
      },
      {
        "expectedAnswer": 57,
        "givenAnswer": 57
      },
      {
        "expectedAnswer": 50
      }
    ],
    "secondTrialTime": 20.729416012763977,
    "thirdTrialStartingValue": 98,
    "firstTrialStartingValue": 88,
    "thirdTrialTime": 17.931267976760864,
    "practiceTime": 18.905928015708923,
    "firstTrialValues": [
      {
        "expectedAnswer": 88,
        "givenAnswer": 88
      },
      {
        "expectedAnswer": 81,
        "givenAnswer": 81
      },
      {
        "expectedAnswer": 74,
        "givenAnswer": 75
      },
      {
        "expectedAnswer": 68,
        "givenAnswer": 68
      },
      {
        "expectedAnswer": 61,
        "givenAnswer": 61
      },
      {
        "expectedAnswer": 54,
        "givenAnswer": 52
      },
      {
        "expectedAnswer": 45,
        "givenAnswer": 45
      },
      {
        "expectedAnswer": 38
      }
    ],
    "subtractValue": 7
  }
}