I got caught out by exactly this, and I'm not exactly tech illiterate. what made it even more annoying is by the time I'd realised what had happened, it was practically impossible to get the files back out of OneDrive (since I decided that this was enough Windows for me, and went back to Linux), since the webui does NOT handle downloading lots of small files well, and you just end up getting a partially complete zip…
I wonder if rclone would have behaved any better than the web UI.
So you are completely stuck if you have too many files. Like I had. I used to keep pictures on onedrive, and used 6 user license. When the license expired, they locked me out completely. I couldn't download my own files! And the web UI is a crap.
So had to pay again for a year, this time I backed up all files locally.