Why can I only install certain APK files?

[Android Central Question]

I accidentally updated my phone to Android 11. Also youtube, which had previously been running version 14.43.55. I installed that version via APK when I bought this phone a year ago. At that time it was on Android 10. Now it's on Android 11. When I try to reinstall the APK now, it gives me the "app not installed" message. When I try to download any other APK file for version 14.43.55 or similar, I get the same message. I thought maybe it was because android 11 wasn't the target version, however when I tried to install a newer APK, that was targeted for Android 12, which I don't have, it worked. I just want to download a version of youtube similar to 14.43.55 (Oct. 2019) Storage isn't the issue, I've tried rebooting the phone, disabling play protect, allowing apps from unknown sources, and resetting app permissions.
Any help is greatly appreciated.
Device: Samsung Galaxy a51 (Android 11)

 

[mustang7757]

Where you getting the Apk file from?
What version is the YouTube app currently on ?
U can go only to the same version or slightly higher because the YouTube app cant be completely uninstalled.

I'll leave a Link to register so you can communicate here, As a guest account you can only post questions but can't reply
https://forums.androidcentral.com/showthread.php?t=409154

 

[B. Diddy]

Welcome to Android Central! Is there a particular reason you want such an old version of YouTube?