[danburzo]

Yes, a smart server (that does more than serve static image assets) can do the heavy lifting and alleviate some of the HTML markup complexity.

It has the `Accept` header as a guide to what image formats the client supports, and with Responsive Image Client Hints[1], it can opt into more info from the client (device pixel ratio, image layout width, viewport width).

Without relying on server features, `<picture>` with `<source type='…'>` is the way to serve images in newer formats without breaking in less capable browsers.

It’s interesting that `image-set()`, the CSS sort-of counterpart to `<picture>`, bakes in the media type along with the resolution in a single syntax [2]. Which you could potentially see happening in `srcset`, but it makes the descriptive/prescriptive boundary a bit blurry, so it would complicate things IMO.

[1]: https://wicg.github.io/responsive-image-client-hints/ [2]: https://developer.mozilla.org/en-US/docs/Web/CSS/image/image...