It’s not necessarily that the movie is going to Disney+ that they’re upset about, it’s that they aren’t being given the Premiere Access treatment. It’s creating a perception that Disney seems to view Pixar as a lesser brand that doesn’t deserve to be in the same category as Raya, Mulan, or Black Widow. And it's not really a good look to send two films in a row that feature different cultures straight to streaming.
I get that. I also get the thought on Disney's end that Pixar will be a big draw as an original for their four-quadrant audience.
I think there's a distinct difference on the part of Disney Executives, who now no longer care what the product is (even Black Widow is going Premier Access), they see everything as a possible streaming option now. The creatives however create these films for theaters and I get their frustration in it being a Disney+ original instead of at least being Premiere Access/Theatrical like Raya, though for sure.