This has been one of the wrong mind set the new beginner in the cryptocurrency space are failing to understand, the backing up seedphase of a wallet on google drive is like making it more faster an easier for scammer to attack the wallet
How to back up a seed phrase? is a very detailed and good guide for wallet backup practice, with Dos and Donts.
Backup your wallet in wallet file, text file on any third party platform is a risky practice. It's because you can not control what will happen with that platform, not restricted to Google Drive in particular or Cloud storage services in general.
Their platforms can be hacked, data can be leaked through hacks or by their internal staffs who don't have good responsibility and morality.
Another risk is your account can be hacked and information inside exclusively your wallet backups can be stolen too.