Savage Wombat
Hero
I mean, good grief, in one of the preview articles, they changed some minor planar creature, Shemeska brought up a single article from a Dragon magazine in the 90's as a reason why the change could not be made.
Quoted because this is really your point.
Canon has inertia because it's canon. Whether it's "too much" is a matter of opinion.
From what I've seen, lots of people have personal opinions on how much canon they want in the official material. And they argue for their preferences. But what I keep seeing you do is complain that Planescape fans argue strongly for their favorites. If you were arguing that WotC favored Planescape over everything else, I might agree with you more. But you specifically seem to want them to hold their tongues on this particular issue.
Just say "I prefer my monsters without so many preconceived notions of their identities" or some such, and the argument is over. It's when you say "Planescape fans always want to have their way" that I feel I need to argue with you about this.