As of July 17, 2023, Netlify's built-in asset optimization feature is deprecated, with the goal of enabling better experiences in other areas. The feature, which bundles and minifies CSS and JavaScript, compresses images during build time, will be phased out, with new sites unable to use it as of August 24, 2023. On October 17, 2023, the feature will be at end of service, after which Netlify will still build and serve sites but without running optimization on new builds, potentially leading to slower load times. Users can test the impact by creating a branch with `skip_processing = true` in their netlify.toml file or by using dedicated bundling tools like webpack, Parcel, or Rollup for managing and optimizing assets before deploying them to Netlify.