TLBGT I haven't noticed too much of a performance loss, actually (assuming this is because of aforementioned single-file-linear-processing). However, a "syncing" tool that does not "sync" is ... out-of-sync to me (the latter less being tongue-in-cheek but asking "ladies and gentlemen, we're in 2021 by now, not in 1981, shouldn't multi-access-sync work by now?".
Plus, coming back to issue one, if I am the only user with the only account accessing files, why would there be an issue in the first place. Don't get me wrong, I am a software dev, I know "why", but ... WHY!
Why not have an "open count" for OneDrive files? After all, it IS tightly (too tightly I say) integrated into the OS. Why not have a sub-ID per user, where each access gets its own sub-ID, so that out-of-sync-state can be one-id-multiple-sub-id? Why not have a WORKING "flag" system for files that are open across different systems? Why not ... come on, even I could probably fix a few issues and I am an old man with no clue ...
Apologies for the rant. I just wish Ankita Kirti would take notice that her over-the-top-praise of MS' tools isn't echoed quite the way she probably expected.