> The executives just gave up once all the other browsers had added support.

The big turning point seemed to have been Adobe adopting JpegXL as an approved image compression algorithm for the upcoming PDF spec. update. With that, since all browsers seem to also want to be PDF renderers, meant they had no choice but to include a JpegXL decoder. The win, if there was one here, was that the decoder they have to ship anyway now was exposed for use by <img> tags as well as by the PDF renderer.