Dear UX specialists with no knowledge of statistics: you can use the MAB algo with 2 choices, no problem. And it is a better way of getting 'the right choice'.
Dear statisticians: there's more to life (and to UX) than A/Bing (or MABing) everything
This has obviously been standard procedure for a while now. I see this on almost a daily basis. Afraid your comment on a HN thread won't get enough traction? Make a blog post instead, meant expressly for submission to HN (or reddit, or ...)