Whenever I look into the modern formats excited to save 50% on bandwidth, I realize I'd have to spend 50% more on storage since I still need my fallback to JPEG. WebP is probably the best supported but isn't available on slightly older Macs or iOS devices. There are tons of iOS 12 iPads and pre-Big Sur macs in service.
given the cost difference between storage and bandwidth, that's probably a worthwhile tradeoff. Especially given the common usecase of store once, send many times.
Use AVIF instead. An image in AVIF is half the size of an equivalent JPEG. Chrome already has it, and full Firefox support is imminent.