Bun is much much more lighter than node or deno. If you don't mind the controversy around the rust rewrite, it's objectively the better option in most cases.
I made a fairly straight forward webapp with Bun and let Claude check whether it was actually better than Node. Nope, Node consumed less memory and used about the same CPU as Bun. I didn't switch, because it costs tokens, but Node's reputation seem to be based on its legacy more than on today's use.
A month before the rewrite I was hitting soundness bugs on fairly trivial JS code. I remember right, under HMR re-exports of module variables caused a snapshot, and importers of the reexport saw stale values.
I reported it, watched robobun write an unhinged +300 -0 patch which quickly got LGTM'd and merged.
I hope now that we've moved past AGI and into the ASI era things are better.