Why is JPEG the de facto lossy compression format for photos? It always bugs me that video formats get something new every 5 or so years yet photos are in JPEGs for decades.
1. widespread support
2. "good enough" compression
Formats that compress better, like HEIC and webp, are only ~2x better, have sparse software/hardware support, and are likely to be patent-encumbered.
If I had to guess, formats that support HDR or other features haven't seen adoption due to a lack of widespread display support (in the case of HDR) and a lack of user interest.
See https://en.wikipedia.org/wiki/Comparison_of_graphics_file_fo... for a bunch of examples.
Video formats get something new pretty much by necessity as resolution and quality increases mean older formats strain links.
Serving a 100k heif instead of a 500k jpeg is not going to materially change much.