It's one of those annoying internetisms that people often pick one part of a post or idea, take it out of context, and respond to that misrepresentation.

It's a bit like a straw man fallacy.

It happens a lot less often on HN though in my experience.

Right after the bit you quoted I noted that WB buying an expensive car doesn't even things out.

The idea of sales tax as a replacement for income tax isn't new or lacking rigor. Over the years it's had a lot of support from both economists and politicians. The math, at least on the surface, does work.

Personally, I haven't spent enough time looking at it to have a lot of conviction one way or the other about it's viability.

But it's an interesting idea that isn't invalidated by comparing cars.