I am wondering if Rails moved to esbuild a little too early.
The Rails https://github.com/rails/jsbundling-rails gem lets you pick between esbuild, rollup and Webpack. If Turbopack ends up being popular then jsbundling should be able to support it.
The nice thing about Rails now is there's no massive direct integration like Webpacker once was. Now we can basically use the JS tool straight up and Rails will just look at assets in a specific directory, it doesn't matter what tool generated it.