Most of which has nothing to do with compression format, to be honest. No image compression format is going to save us from websites that use 2000x2000 sized photos for 200x200 author thumbnails.
Maybe I should write one, I guess.
https://github.com/metalabdesign/sharp-loader
https://github.com/herrstucki/responsive-loader
https://github.com/tcoopman/image-webpack-loader
(and many more, just grabbing a few examples)
Something that I've not seen is a plugin/loader that will automatically use the <picture> tag to make available multiple auto-generated source images and a fallback <img>. It'd be great to be able to
import myImage from 'res/img/my_img.png'
and have myImage be a string like
<picture><source srcset="[generated-name-of-my-image.webp]"><img src="generated-name-of-my-image.png"]></picture>
Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith.
This sounded like an obvious truth but I think you're wrong!
JPEG has progressive rendering, so a browser could easily decide to stop once it has rendered enough for the image size. Once you zoom or if it's used elsewhere, it can render a little more.
However, as TFA mentions, better compression is currently a double-edged sword, because the CPU has become a bottleneck again: even top-of-the-line Android phones have weak Qualcomm CPUs, and sites use so much JavaScript that even high-end machines can struggle.
So we may end up living with JPEG for a few more years. This format has been designed when CPUs had 25Mhz, and we've had over 25 years to optimize the implementations, so we get a lot of bang for the buck from it.