No official Google Drive client is available. But, you have good alternative methods and tools to use it on Linux!
I'm soon going to transition to full Kubuntu and remove Windows from my PC. I've been looking for alternatives to a lot of the stuff I use and this one was a bit problematic. Or so I thought.
I'm also going to migrate from Google to Proton at the same time and it looks like some of these tools support Proton Drive as well!
Your comment made it sound like it's a privacy concern that there's a plug-in in Gnome or KDE or that there are apps that use the Google drive API, which is not the case. It's not even code that's developed by Google.