Have you looked at Obsidian? It offers paid sync service which hasn’t lost a file for me for the last year or so I’ve been using the sync service.
At least standard notes produce conflicting copies when collisions occur. Obsidian simply overwrites the old with the new, which makes it completely unusable to me. This is a non-issue if you always have reliable internet connection, but that's not always the case in practice. I don't like the way standard notes handles it, but at least I've never lost any notes with them.