I have read and followed along over the years with issues for TM backing up to a non-Apple destination, usually a NAS.
Issues come and go regarding TM failures. Luckily there are some
smart folks who share challenges and fixes.
Some folks—after having found and resolved the backups being reported as corrupted, forcing starting over, losing all history, and being without a backup for a long period—see issues return with an OS update.
Others seem to think wifi is the issue, and report more success with clients and destination being wired.
It feels like Apple changes something like (AFS or SMB spec) that breaks stuff again. Hard to prove, with no easy error logging to diagnose. Apple doesn't really broadcast functions or specs to anyone. Makes it harder to diagnose, plan for change, utilize all the functionality...and (for me) to trust TM for long term archiving.
Synology supports TM backups, but you don't have to look far to
find questions and gripes about the same problem. My impression overall is that TM to supported third-party NAS works...until it doesn't.
I had wired iMacs backing up to Synology NAS for months. Out of the blue, file corrupted issue. Was it a MacOS patch or update? A Synology patch or Update? Something else?
Long story short, If it won't run reliably for more than a few months, for me it is too much of a bother to troubleshoot and fix, even if the issue is only once or twice a year (or per OS update). So far (more than a year now) Drive backup has been chugging away with only very minor file specific issues; nothing that required wiping a data set and starting over.