It's a continuation of a trend in which open source projects mimick the functionality of a tool called Firebase that Google bought in 2014 and is now part of Google Cloud (see also supabase and pocketbase). All these projects seem to be sort of like Redis in as much as they stick a datastore behind an API saving users from needing to use SQL and offering them a higher level API instead. And it also seems to do some sort of auth things.

I think it's meant for people who want to build a front end without building a backend.