Anything can happen. We're always at the mercy of the busines decisions of our technology providers. In this case Google can keep the protocol stable and stop supporting the client to the point it stops working after an update of your distro. If you want to be nearly 100% safe you self host whatever the price and the time you have to pour in. Personally I use Syncthing over my home network.

rclone uses google drive's APIs to talk to them

Google can always change the protocol and stop supporting a native client too.