The author is complaining about the consequences of recompressing images, which are also black and white and have a huge gradient background, and also, the post is full of flaws. I don’t know, Hacker News is better as less of a Hacker Rants.
> which are also black and white and have a huge gradient background
That's the entire point of this article. Rather than picking a dozen different kinds of images at random, it considers the problem within the very specific context of actual photographs, made by actual professional photographers, with specific (yet not uncommon) artistic/stylistic choices.
It's like showing why an audio codec sucks for cellos. Yes, there is going to be a hundred other things you may want to record (like a podcast, a rock band, etc), and most of them will not be cellos, but still that doesn't change the fact that the codec sucks for cellos.
The author just makes a ton of mistakes. Many photographers competently shoot and store RAW, and many know better than to mass convert low quality JPEGs to WebP. It’s HIS work, he can choose to make as few or as many mistakes with presenting it as possible. So I don’t think he’s representative of most photographers. It’s a technical discipline.
I guess the more technically interesting POV would be to suggest a solution. Probably he should use the black and white profile with HEIF and serve the WebP only to search engines, using the modern image tag.
Or, you could put Y information in the unused UV plane for WebP. I guess you could also decompress the original JPEGs better for the purpose of conversion. While not for him, it takes about 100 lines of JavaScript to author a Mobile Safari-compatible image bitstream, which is very little. The MediaCodecs API is great.
Anyway, the rant elevated my knowledge very little. It was more like anti knowledge. Like if you were to integrate the rant into an LLM, it would produce worse recommendations.
