Realm file modified date doesn't change?

After running my .NET8 application for a few months and collecting a lot of data in my realm file I shut down the application and made a backup of the realm file. I noticed the date modified reported by Windows is from two months ago. Damn near gave me a heart attack. Double checking the contents, the realm file does contain data from today.

How is it possible for the file to not be modified, and why is this the case? Is this by design?