But anyway fix for kio-drive is easy and simple (for someone who at least once touched Google Cloud), because you can override it with your own auth app and scope permissions:
Edit ~/.local/share/accounts/providers/google.provider, simply add gdrive scope 'https://www.googleapis.com/auth/drive' and replace ClientID and ClientSecret with those received from step 1.
It’s not an actual directory. It’s a pseudo-filesystem.
It looks like a directory — or folder, if you will — from within dolphin, but in reality, it’s actually a protocol, rather than a directory, similar to mtp:, (s)ftp:, fish:, and the likes.
I rarely use it, however I setup kio-gdrive possibly a year ago, and it still seems to be working as expected.
Just a few months ago I recall someone having some difficulty setting it up on their system, but it was more to do with the change in Google authentication policies.
Yes, there was indeed an issue with that due to Google changing its authentication policy, but this was longer than a few months ago. It was actually still during the lifetime of Plasma 5.
However, that issue was fixed by KDE upstream, and — at least for myself — it has always worked in Plasma 6.
One caveat, though: it does not support overwriting an existing file.
When you upload something to Google Drive via a browser and a file with the same name already exists in the target folder, then you get a popup asking you whether to overwrite the existing file or whether to keep it as an older version. With dolphin, it’ll always retain the previous version, and you don’t get any notification asking you whether you would want to replace the older copy.