[css-images-4] Should gradients even interpolate?

In Images 4, smart interpolation of gradients is defined: https://drafts.csswg.org/css-images-4/#interpolating-gradients. This spec text has been around for several years, but afaik has never been implemented; browsers instead just interpolate gradients as generic images (cross-fading them).

We just agreed (in https://github.com/w3c/csswg-drafts/issues/1332#issuecomment-910891011) to add easing functions as <color-stop-hint>s, which would involve some more involved edits here - we'll have to define how to interpolate easing functions. That's not a difficult thing, but it's still work, and if UAs don't expect to actually implement smart gradient interpolation, I'd rather avoid doing that.

So, question to implementors: is there any intention to actually implement the smart gradient interpolation? Or should we give up on it and define that gradients interpolate as generic images?

(tagging @dino because they brought it up in the call)

Start with the CSS Images 4 “Interpolating gradients” section and the linked csswg-drafts issue #1332 discussion about color-stop hints. Determine whether implementors intend to support smart gradient interpolation; done means recording the Working Group decision and aligning the specification text with that decision.