docs: improve why not bundle with esbuild (#14998)

Author: patak-dev

docs/guide/why.md

@@ -53,7 +53,7 @@ Ensuring optimal output and behavioral consistency between the dev server and th
 
 Vite's current plugin API isn't compatible with using `esbuild` as a bundler. In spite of `esbuild` being faster, Vite's adoption of Rollup's flexible plugin API and infrastructure heavily contributed to its success in the ecosystem. For the time being, we believe that Rollup offers a better performance-vs-flexibility tradeoff.
 
-That said, `esbuild` has progressed a lot in the past years, and we won't rule out the possibility of using `esbuild` for production builds in the future. We will keep taking advantage of new capabilities as they are released, as we have done with JS and CSS minification where `esbuild` allowed Vite to get a performance boost while avoiding disruption for its ecosystem.
+Rollup has also been working on performance improvements, [switching its parser to SWC in v4](https://github.com/rollup/rollup/pull/5073). And there is an ongoing effort to build a Rust-port of Rollup called Rolldown. Once Rolldown is ready, it could replace both Rollup and esbuild in Vite, improving build performance significantly and removing inconsistencies between development and build. You can watch [Evan You's ViteConf 2023 keynote for more details](https://youtu.be/hrdwQHoAp0M).
 
 ## How is Vite Different from X?