The only implementation which is going head on with MRI is JRuby. I've heard from JRuby implementers that keeping the runtime compatible with MRI is an uphill battle. I don't know if AI can help this cause.
I did some digging into Artichokes sourcecode to get inspiration for making a Ruby like language in Rust. But I found the codebase a bit complicated and ended up taking more inspiration from mruby instead. It's deeply segmented into different crates like many Rust projects are.