Oh sorry, I thought you were asking why I had the belief that it was censored, not what I thought the reason for it to be censored was. Ambiguous wording and all that. Apologies.
It's likely censored because Xi Jinping finds it offensive. I had assumed this was because of Pooh's weight, or his intelligence, or general mannerisms. It could be due to his color I suppose, but it's not the only explanation. If that's actually the reason it would be a lot more distasteful to refer to him as Pooh.
It's my opinion that "mannerisms" don't really hold much weight, same with "intelligence." The remaining two are weight and color, and there's absolutely nothing saying it can't be both.
Asian people don't actually visually look yellow, that's just racist charicature. If the comparisons are purely visual then it would be about his weight, especially around his face.
And the comparisons aren't necessarily only visual. Winnie the Pooh has a well-known personality and behaviors, and as a meme there isn't necessarily a re-comparison being made every time it's reposted. Note that Pooh images are more popular than any other comparisons, because it's an existing meme.
I think you're tying yourself into a logical pretzel here, are you going to tell me blackface isn't racist because nearly nobody has that pure black use in minstrel shows? This seems like incredible displays of mental gymnastics, rather than taking occams razor.
Fair enough. However, I think it's worth pointing out that the most vocal users of such iconography, when confronted with even the possibility that it may in fact be racist to depict a chinese man as a yellow bear (curiously, usually depicted wearing a red shirt, like the flag of the PRC), they tie themselves into frothing logical pretzels to defend their usage, rather than shifting to any other clearly non-racist yet still insulting caricature.
Note: absolutely not saying the author of Pooh was making anti-China iconography way back when, I am pointing out modern usage.
His shirt being red referencing the PRC is actually a great non-racist visual connection. And of course they wouldn't suddenly switch to another caricature; the meme is Pooh, so that's what they're going to use.