Nothing is 100%. I've always questioned using the cloud without encryption. I use the services like offsite backups.
The bottom line is that it is your data and your responsibility to ensure your work is backed up and recoverable.
Really for how long Google has operated drive, it has as good a record as one could ask for. Stuff happens, Murphy's law and stuff.
That can be OK as long as it is not the same cloud provider.
I do think there is a lot to be said for backing up local data to the cloud, and cloud data to local storage.
Its a good start but still falls short of the 3-2-1 principle. You should have an additional backup that is air-gapped.
I thought google was keeping those for me
People are downvoting you but i regularly take backups of my google account data - emails and drive. Poop happens and better be ready for when it does.