Some of the "errors" you point out are only barely even errors, like missing `alt` attributes (nice for accessibility, not so helpful when the image isn't actually content).

Others like using empty trs for spacing is just old-school HTML wrangling. Could it be improved? Sure. Does it actually matter? Only barely.

Many of the errors are dupes; if you roll them up there are significantly fewer "errors". Which makes sense, because the HTML on HN is trivial to begin with, by design.

What was the point, even?