Splash, the 1984 comedy classic about a man falling in love with a mermaid, contains a couple of shots of Daryl Hannah's butt as she walks/runs away from the camera. There's nothing suggestive or lascivious (you could argue that Tom Hanks' character Allen is ogling Madison as she runs into the water, but we're really playing devil's advocate there), but Disney clearly feels some innocuous ass-shots are a step too far.
Disney+ has altered the offending shots for their cut of the movie. The first awkwardly crops the screen as Hannah is jumping over a rail, but the second goes so far as to digitally augment the character's hair so it's long enough to cover her rear end.
This is understandable from one perspective as Disney+ is a family-friendly service, but when you consider some of the adult themes, bad language and surprisingly brutal violence (Loki getting his neck snapped in Avengers: Endgame, for example) that pops up in the MCU, this definitely seems like an overreaction.
Then again, censors have always taken a harsher stance on sex and nudity than violence, so it's probably not that surprising.