That said, in the context of showing off your photography I can understand considering these kind of artifacts undesirable, even though they're perfectly fine for a lot of other uses. On my own website I spent quite some time downgrading my mugshot to be as small as possible without too many artifacts – it's now 4.9K in WebP, vs. 9.2K in JPEG before. Maybe that was a tad obsessive though...

I do think the author doesn't quite appreciate that most people are not photographers, and that for most images quality doesn't actually matter all that much.