A more efficient image format helps everyone on the web. We’re looking at 30-50% fewer bits sent over the wire for the same image quality. Massive bandwith savings for everyone. JPEG-XL is basically a better version of what Google was already trying to do with WebP, and a suitable long-term replacement for all image formats currently in use.

* much faster decoder/encoder than avif

* Much better quality at high bpp (avif performs better at high compression levels, means shitty quality images can be much smaller, while high quality images either don't compress well or loose quality a lot)

* Best in class lossless compression, to replace png

* Progressive encoding

* Ability to losslessly reconvert existing jpegs for 20% free gains

Google Research (which, if I remember correctly had member working on jxl spec and did reference implementation) has much more freedom, and has already been cleared to work on jxl, than the Chrome Team. They also don't have the same goal. Google Research is also responsible for Brotli and Snappy I believe.

For all we know, JXL might be super useful, and is actively being used, for some project at Google for X, Y, and Z reasons, but the Chrome team doesn't want to add it to the browser for A, B, and C reasons. Google does many thing.

They have a general interest in the quality of the web. More web use is good for Google Ads. This sometimes comes into tension with Google's attempts to control and monetize the web.