But requirements for audio hasn’t changed that much, and overall it’s a much older and thus mature technology, that there isn’t much left to figure out. Consumer CD format with 16bit 44.1kHz has been around for 40 years, and you don’t need much better quality than that. So there isn’t much left to figure out.
But images and videos are different. 20 or 30 years ago you didn’t need to commonly send 20 MPix HDR photos and HD to 4k videos over the internet. Shoehorning formats that were made for 640x480 pictures and tiny silly clipart animations just doesn’t make sense, especially with all the development that’s been made in that time. Newer compression techniques can help, but you can only do so much.