This ship sailed in 2000. We've been hacking custom select boxes since then, so we may as well pave the cowpath. And besides, as a user, I want stylable select elements. Seeing an ugly old select box in the middle of a site where everything is styled consistently is jarring.

And it doesn't get the job done. You can't put stuff like SVGs or complex DOM elements in them, which is a valid use case. Most of the time, when people create custom select boxes, they ignore accessibility. This will fix that issue.