You are again mixing everything the activity is finished, what can be left over is the services and the process.
On Android 15+ after pause they stay active a little long to allow resuming of the playback via headsets.
If you swipe the media session it will go away as all other apps.
What you may face is Samsung restarting the app later and you need to check the option disable media session restoration for that as you could have found too 
For the logs when opening the issue it explains everything as would a simple search
Anyway no need for them since you have confirmed you have Samsung. Just read again this answer if you have more questions.