You are talking about the same company that took a relatively obscure comic like Guardians of the Galaxy and pushed it to the forefront. Same could be said of Iron Man, wasn't a very popular character on his own, though well known in media.
Some of their side characters don't do too well on their own either. Black Widow wasn't super huge, and objectively a pretty simple story with little character development. First venom wasn't a hit either, that they bothered with a sequel is somewhat surprising. Though they are falling a little into the common trope of having the character fight themselves (yes, Carnage is as popular, but other symbiotes was also the threat in the first one)
Follow up Doctor Strange should be interesting, though probably not a huge success.
Thor 4 should be interesting and popular, they've done a good job differentiating him from the basic comic character.
No sign of a standalone Hulk movie (honestly they've taken a lot of the fun ideas and stuck them in other properties, so not really sure where they would go)
You have the Eternals as a shot in the dark for another more obscure comic. They just did Shang Chi (I haven't caught that one yet) Probably the safest asian character they could track down.
Then there is the entire TV section with the What Ifs, and all the various character shows. I don't really think they are leaving anything on the table.
Disney is scrambling to create new IP as a lot of their traditional stuff is going to start going public domain here in a few years. Mickey Mouse in 2024. So creating all this content means the contemporary likeness of these characters they can keep around for the next several generations (A lot harder to do with a more simplified character like MM)
Disney needs to get someone passionate in charge of any new Star Wars plans, or stick to TV.
DC TV and Animated, as usual, are far better than the movies. They need to take a serious look at hiring some of those writers to make their movie screen plays. Snyder Cut was okay, certainly better than the first release, but still has a lot of flaws.