Please avoid this kind of unconstructive snark. I'm prone to it myself when discussing this subject, but I try to avoid it when discussing accessibility with a broad audience like HN. I want to meet mainstream developers where they are, figure out what prevents them from making their applications accessible, and do something about it, not just guilt-trip them.
I actually use <button> with appearance:none specifically for accessibility. You get all of the benefits of a button's accessibility, focus, click events, normal tabbing, etc, and can use them for things like toggling an accordion of content or showing/hiding a mobile menu. Better than a div because you don't need aria-role, and better than a link because it is not taking you anywhere.
As pointed out up thread, developers and designers often skip using <button> because it is hard to style just right. Using appearance:none resets the style but not the accessibility behavior.