I wouldn't say so - CN has aired that a few years ago (twice, if I remember correctly, once on "Late Night Black and White" and then on "The Bob Clampett Show")

-Pietro:daffy:

Africa Squeaks
Norman Normal
The Door
Injun Trouble (:coolcat: )
Philbert (Three's A Crowd)
Little Go Beep
Father Of The Bird
Boom Boom
All the Doyle LT's except Whizzard Of Ow

CN has aired that one a handful of times back in the old days and it has appeared on several public domain compilations to boot.

-Pietro:daffy:

Yeah, but not many people taped it and all those PB videos are out of print.

Norman Normal
The Bosko Shorts
goofy Geer
and the buddy shorts are on my list of rarest shorts

Heh. Having watched the Nickelodean years incessantly while they were on, I can never think of the Bosko and Buddy cartoons as rare. Why, we saw them all the time! I saw Buddy the Woodsman so often I almost have it memorized, which is a shame, as it's... well, a Buddy cartoon. :buddy:

My picks:

NORMAN NORMAL
THE DOOR
AFRICA SQUEAKS
INJUN TROUBLE :coolcat:

"All This and Rabbitt Stew" with the "Negro stereotype" hunter is on the rare list.:bugs2:

I wouldn't call this one particularly rare. In fact, it's quite commonly found on filesharing platforms, and I think there's more than a handful of public domain collections that contain this short.
I've never seen Porky's Pooch, for example, but I think I just haven't tried hard enough to track down this one. I believe it's a managable task to compile a collection with all classic Warner Bros. cartoons within a reasonable time (with the possible exceptions of Little Go Beep right now).

Perhaps Thad is closest with his list of cartoons uncut; but what about this one:
A version of Dog Daze (1937) including the scene near the beginning with the dog stopping by the pole? (Is there really a cut?)

WW
(proud of his 1969 Injun Trouble copy)

A few years ago, they had a bunch of new PD tapes at a used book store here in Texas and this toon was one of the three that were on the tape. I bought one (at the time I hadn't seen "Rabbit Stew") and as I stood in line I noticed that there were at least six other people buying the same tape. I had to go back the next day to pick up a book that had been ordered for me and I saw that they had sold out their entire stock of this one PD tape in just two days. I'm thinking that maybe it's not the majority that's so PC, but the ones who are this way make such a fuss that it just seems that way.;)