Was it ever a reasonable choice? At the time the choice was made the tooling ecosystem was already split between Rust and JS, and by putting TS in Go they chose to split it three ways. Why not split it 4 or 5 ways then? The pressure will always be towards less duplicated work.
The only real choice of language to build the next generation of JS tools in is JS. Anything else is a vote of no confidence in ourselves.
It's ok for a language (JS in this instance) to be good in a domain but not good in all domains. Pulling a language in every direction forces it to make compromises that hurt its applicability in specific areas.