A modern programming language that makes developers happier.

kotlinlang

I think a lot of the issues around the negative aspects are shared architecture are organizational. Airbnb and RN had a lot of issues that had nothing to do with "sharing code". Under the hood, android and ios are very, very similar, so sharing logic and architecture is absolutely doable. It becomes a lot more difficult if you have 2 separate teams who aren't really focused on making that work (imho). When RN is a failure largely because there's an expectation that adding JS means non-native people can add productivity to these native projects, and people get upset when they realize its a lot more work and BS than expected. Also, RN and "shared architecture" platforms are wildly different in how they work, but eh.