[red_trumpet]

Better typography helps with reading. The same reason someone would complain if this was typed in Comic Sans. Also the images don't scale well, so if you look at this with a high resolution display, either the images are too small or not sharp.

[thaumasiotes]

Well, having gone and looked at the website, I'd have to agree that KaTeX would be an improvement, but not for reasons that relate to whether the math is rendered as an image.

Rather:

- The background of the math images is white, which doesn't match the background of the website;

- The baseline of the text in the images is not aligned with the baseline of the surrounding text.

I was imagining a more-competently-put-together website.