Yes the point isn't esbuild will have magic pixie dust that makes nodejs AST processing magically faster--that's objectively impossible. The point is you can migrate to the new system over time without losing critical plugin functionality right now. It's not to live in a steady state with old slow nodejs plugins.

Having now switched several projects from webpack+babel to esbuild, with a bunch of plugins to replace various bits of resolution magic, SCSS compilation, and more, the performance gains are consistently astronomical. Simple builds go from taking several seconds to consistently completing in an unnoticeable amounts of time. Full rebuilds are still significantly faster than incremental (--watch) builds used to be.

Setting this up takes a bit more work than for webpack, and it's easier to run into limits on what's reasonably possible, but I don't intend to ever go back.