Disney paid 4 billion in cash and stock for Lucas. Six years later, the movies have made about that much. They paid the same thing for Marvel in 2009, and they paid 7.5 billion for Pixar in 2006. Those are both seen as brilliant moves, despite the fact that "The Good Dinosaur" only made 300 million and the first Captain America movie only made 176 million. One underperforming movie does not doom a franchise.
Technically, Star Wars had TWO underperforming movies (Last Jedi also was a bomb ESPECIALLY in China, pretty much the one audience that exceeds America at the moment in Hollywood’s view. And to add insult to injury, based on how JJ Abrams behaved where he effectively pulled the same stunt that the infamous 2016 remake of the Ghostbusters pulled by inferring its audience was “afraid of women” suggests even HE knew it was a bust in America as well). And apparently Star Wars Resistance got pretty bad reviews from what I heard. In fact, it’s not just the movies, even the actual merchandising for Star Wars has been bombing lately, having a massive decrease in revenue (and if that’s not bad enough, apparently it’s bad enough to actually affect the mainline Disney products like Frozen): https://www.oneangrygamer.net/2019/01/star-wars-revenue-takes-hit-across-video-games-merchandise-comic-books/75132/ In fact, Disney’s doing so badly in terms of sales that, at the time that article was written, the MCU is pretty much the only thing keeping Disney afloat, and based on Captain Marvel’s current reception, I’d argue it’s probably not even going to have that keeping it aloft any longer. I’m guessing Iger’s probably going to need to consider resigning if he doesn’t want the shareholders to give him the same fate that Michael Eisner got (being ousted, in other words).
Also, the first Captain America movie was not made by Disney (heck, it predated the deal selling the MCU over to Disney). If you were meaning the Avengers, then we’re getting somewhere.