This is what it was for me as well. Which was tough to diagnose, since I would hit "download" in a random gdrive folder, and just literally nothing would happen. It would just sit there. No message, no error, etc. So frustrating. Once I figured out you had to turn 3rd party cookies on, it worked fine. I quickly moved all my work stuff to box.com and personal stuff to protondrive and just stopped using gdrive altogether.