No, I don't consider any criticism of changes to be baseless. But I expect an argument beyond emotional/nostalgia-driven appeals or platitudes about what Walt would've done.
As another poster said, you seem to be setting up a straw man here by saying that anyone who doesn't agree with you is telling you to "step in line and love every change," because this is not a binary choice.
My thoughts on single-IP lands in castle parks: Why not? There's no reasonable rule, nor should there be, that the castle parks must retain the exact parameters from 70 years ago. Their designs and offerings have evolved with new iterations -- I don't see why if Disneyland Paris changed the formula by having Discoveryland instead of Tomorrowland in 1992 that the castle parks can't include single-IP lands now, and they already have in Shanghai and Hong Kong.
All that matters to me is the execution.