The only thing I agree with here is that Prettier should remove the /> on tags that don't self-close, i.e. it should turn <div/> into <div>. Other than that, the use of self-closing tags is a cross between an aesthetic and a reminder of which tags self-close. I work with HTML pretty rarely, so while I can remember that <br> is self-closing, I don't necessarily remember what other tags work the same way, and the inclusion of /> in HTML I'm reading is a good reminder that it's self-closing.