I mean this reminds me of Firebase v1 and FoundationDB I think both of which have a favorable reputation for quality in both design and implementation. I do think there's something to be said for being forced to code against what operations are actually fast in your DB. Once it works you can be reasonably confident it will also be fast rather than the typical RDBMS experience of getting an abundance of rope with which to hang yourself with. You often won't find out until it's already load bearing that your query doesn't scale.