Whatever are you referring to? JPEG XL had already been merged into Chromium, prior to being removed again (without a proper reason ever given). As far as I know, the JPEG XL developers have offered to do whatever work was necessary for Chromium specifically, but were never taken up on the offer.
Same thing with Firefox, which has had basic support merged into Nightly, and a couple more patches gathering dust due to lack of involvement from the side of Firefox. Mozilla has since decided to take a neutral stance on JPEG XL, seemingly without doing any kind of proper evaluation. Many other programs (like GIMP, Krita, Safari, Affinity, darktable) already support JPEG XL.
People are not getting upset because projects don’t invest their resources into supporting JPEG XL. People are getting upset because Google (most notably), which has a decisive say in format interoperability, is flat out refusing to give JPEG XL a fair consideration. If they came up with a list of fair conditions JPEG XL has to meet to earn their support, people could work towards that goal, and if JPEG XL failed to meet them, people would easily come to terms with it. Instead, Google has chosen to apply double standards, present vague requirements, and refuse to elaborate. If anyone is ‘preventing even foundational elements of a successful effort’, it’s Google, or more specifically, the part that’s responsible for Chromium.
It also doesn't help that the Chrome team doesn't seem to apply the sam standard to other formats - webp, avif, brotli etc. were all rushed through while providing a much more questionable benefit and having only very limited support outside the web.
I don't think that is accurate. Brotli was added first to Firefox. It took 9 months longer for Chrome. Brotli has many other uses than content encoding in the web.
I read the parent post as saying that this is the problem, i.e. that "complete" support is a mess, because AFAIK even the reference implementation is incomplete and buggy, and that then getting angry at the consumers of it is besides the point and won't lead anywhere (which is what we see in practice).
Browsers supporting a format "a little" is almost worse than not supporting it at all, because it makes the compatibility and interoperability problems worse.
Same thing with Firefox, which has had basic support merged into Nightly, and a couple more patches gathering dust due to lack of involvement from the side of Firefox. Mozilla has since decided to take a neutral stance on JPEG XL, seemingly without doing any kind of proper evaluation. Many other programs (like GIMP, Krita, Safari, Affinity, darktable) already support JPEG XL.
People are not getting upset because projects don’t invest their resources into supporting JPEG XL. People are getting upset because Google (most notably), which has a decisive say in format interoperability, is flat out refusing to give JPEG XL a fair consideration. If they came up with a list of fair conditions JPEG XL has to meet to earn their support, people could work towards that goal, and if JPEG XL failed to meet them, people would easily come to terms with it. Instead, Google has chosen to apply double standards, present vague requirements, and refuse to elaborate. If anyone is ‘preventing even foundational elements of a successful effort’, it’s Google, or more specifically, the part that’s responsible for Chromium.