JPEG XL Format
This format is lossless by default, supports bigger sizes and more colors than the other new formats, supports incremental loading, is backward compatible with JPEG, and uses relatively little processing power to create and to view. It is also smaller than WebP without taking all the processing power of AVIF or having AVIFs lack of support beyond limited resolutions.
It is so new that few vendors support it. Google just dropped support for it while Apple appears to have just added it. It is also royalty free like the other new formats. I have my most important graphics in this format to future proof my website.
Future of Format
Worst cases scenario it will stay alive in open source products as more obscure and even proprietary formats are already still supported. There is huge support amongst designers for this particular format. It just solves so many problems for them.