Like I said, I was doing that with memcached about 25-30 years back. Nobody had yet built "a service that provides a cacheable request-response interface" to move the db behind.
Just last week I helped one of our devs through "caching" API responses for a "read heavy" use case by saving the responses to S3 and having the web app there instead of hitting the API endpoint and database.
There are a bunch of ways to skin this cat in 2024.
(One brilliant idea I've got bookmarked but haven't (yet) had an opportunity toi use, is a modified SQLite that uses S3 storage and range requests and is compiles to WASM - so a web app can run SQL queries locally and all the usual SQLite stuff "just works" from the warm/javascript's point of view. It _does_ need to be a very read-heavy use case though, because updating even a single row needs to upload the entire SQLite db file into S3.)