Relays operating via http, if done right, would be a tried and tested way to scale nostr. It is a controversial topic though. Some prefer the 'nostr only' approach.
Discussion
I don't think it isn't "nostr only" to have relays operate via http as well. Something like GET `https://relay.damus.com/?kinds=0&author=
Something like this would indeed be very good. The harder thing would be making a clean API on which everyone could agree.