And then the company goes under, or decides your variant of the service is not worth maintaining, or that there is potential for enshittification. All your data, gone. And it WILL happen.
Developers already know how to do this with EC2s, Droplets, Linodes, Azure VMs etc. The process just needs to be more average-person-friendly.
The average person still uses the same password for EVERYTHING, despite say iOS and Android making it easy as pie to just go "generate passwords for me". Telling an average person to have a 3-2-1 backup AND run stuff in the cloud that they will 100% lose the password for is not a battle I see to be won in the near future.