I always thought this, too but then a few years ago I looked through his catalogue and other than some real turds like the Wonka thing, he’s done some fantastic work:
Sweeney Todd
Frankenweenie (feature length version)
Nightmare Before Christmas (didn’t direct, but it’s his film in all other aspects)
Corpse Bride
Big Fish
Big Eyes (not his greatest, but certainly no stinker)
Wednesday
If another director has done those in that time period, they’d be heralded as a brilliant auteur.
The concept and initial character designs were largely Burton’s, but I think director Henry Selick got short-changed by how that movie was marketed. Selick spent way more time and effort on the film than Burton ever did but the studio changed the title to “Tim Burton’s The Nightmare Before Christmas” at the last minute because they knew they could sell more tickets based on Burton’s name recognition. And of course the film also owes at least as much to Danny Elfman as either Burton or Selick—when Elfman saw the final cut his response to Selick was “you did a great job animating my songs!”