S3 is a key-value store with random access and various pricing / limits. If you can make the disk IO part of your DB map to S3 API there is nothing stopping you

S3 is a key-value store with random access and various pricing / limits. If you can make the disk IO part of your DB map to S3 API there is nothing stopping you other than network latency, and ensuring the way you use S3 is cost effective.