Not to totally destroy your point, but LAME can tag mp3s as it creates them, if you give it the options. Do a LAME --longhelp to see them; they're at the end. So it could use a CDDB interface, if it has one, conceivably, but it doesn't, and I can't imagine it ever would, either.

So your point's still valid, even if the facts it's based on are not entirely accurate.