Everyone fully missing the point here. This is the banner image for !linux@programming.dev (that’s not where we are right now for the record), and it has a normal JPEG size of 7.7MB. When it’s served as WebP it’s 3.8MB. OP is correct that this is very stupid and wasteful for a web content image. It’s a triple-monitor 1440p wallpaper that’s used verbatim, and it should instead be compressed down to be bandwidth-friendly. I was able to get it to 1.4MB at JPEG quality 80, and when swapping it out in dev tools and performing A/B testing I can’t tell the difference. This should be brought to the attention of a mod on that community so it can stop sucking people’s data for no reason.
I wrote a short guide on this method recently: https://lemmy.ml/comment/6708735