I've done some digging around here, as well as trouble-shooting on my Note20, but haven't seen this issue described:
The volume setting for notifications keep setting to "silent" after restart. All other volume settings remain the same. This isn't the worst thing, just a tad annoying.
Is it considered a feature? Or is my phone buggy?
Thanks for any insights!
If your phone is misbehaving, it's possible that a third-party app is causing the issue. To figure out what app is acting funny, you can use the Safe Mode feature. In Safe Mode, your phone won't run any third-party apps. This allows you to easily identity and remove the app that may be causing the problem. Give this link a try: https://www.samsung.com/us/support/answer/ANS00062983/
Do you have any third party launchers on your device?
Do you have any Bixby Routines set up on your device?