I have been pretty active in the Splash Mountain threads and don't recall anyone championing him as an individual. One can broadly agree with his view that a retheme is in order without liking him. I certainly wouldn't imply (as he seems to be doing in the tweet you shared) that those who enjoy the current version are racist.
I think what some think (I can’t speak for others just my interpretation) is not that those who like Splash as it is are racist, but those who are dismissing the reasoning behind the changes due to their own nostalgia and dismissing the views of the Black community is a racist tactic, steeped in privilege.
You love splash, I love splash - but we both know the ride has to be changed.