> Plain text is as readable as it is possible to be.

Which is nonsense, of course, just like this site illustrates. Trivial formatting and layout changes make it more readable.

> Besides, this is exactly the kind of site HN constantly laments

And this is exactly the beside-the-point response you sometimes encounter on HN. I'm not a representative of the collective HN, so why does it matter that some other people did some lamenting some time ago?