wilhil I have been through several recent OneDrive/SharePoint moves that delivered similar experiences:
* move just hangs
* move reports it has finished but has left files and folders behind
* attempts to move leftover files and folders demonstrates that SP/OD cannot merge folders as I always get "folder X exists already" messages, leaving me with potentially hundreds of folder X + X (1) + X (2) + .... sets to merge.
In the end I can only sync the folders locally and then do Explorer actions to clean up and then sync upwards. The result is that my OD queue now has 60000 items in it and I'm pretty much hosed doing anything else for the day.
It's all very well to say SP/OD has such and such folder and file limits, but when you're working in these systems you can't see how many files and folders are there unless you're a super-user with time to create special views that tell you what right-click->Properties would tell me in Explorer.