I'm sure that there are power users who are using much more than $20 worth of compute, but there will also be many users who pay but barely use the service.
I would've thought "most" people would be firmly on the free tier, are there any stats to check how common it is? Personally I've had Gmail for 20 years, Android phones for 13 years, Home/chromecast devices but never thought about paying for Google One or any other services.