Most of these were just replacing already existing attractions. They really need to add more without taking stuff away.
Well, it's a little more nuanced than that.
Take Epcot for example. Ellen's Energy Adventure was an embarrassment of an attraction. Maybe they did trick a few hundred people per hour into giving 30-40 minutes of their day to that attraction, but exactly nobody left thinking it was a sound use of their time.
So Disneys choices are: A) spend several hundred million dollars turning EEA into something people actually want to do, or B) spend a little more money to wipe the slate clean and build something entirely new.
Fans would love Disney to do both. Every. Single. Time. But that's not the world we're living in. (Unless you really wanted them to split the budget between a mediocre refresh of EEA AND a mediocre new attraction.) At the end of the day, what's important is ending up with attraction(s) that hold much greater appeal and ideally accommodate far more guests per hour. And Cosmic Rewind accomplished that. So did Frozen Ever After. So did the Nemo dark ride a few years before. (Which we should probably call new since the Hydrolators were closed for years and it wasn't much of an "attraction.")
A similar scenario played out at HS where 3 attractions--backlot tour, great movie ride and lights, motors action--were replaced with 5. I'm aware many people would have preferred to see GMR revitalized, and I won't even argue against that one. Disney did what they did. The other two both seemed to have run their course and took up a LOT of real estate without returning a whole lot of value.
Then there are other factors like attraction operating costs (it's often been said that LMA as REALLY expensive to operate given the specialized skills and equipment involved), suitability of surrounding land, what can you really do in/around existing facilities, etc.
Assuming Muppetvision isn't really on the chopping block, MK, DHS and DAK are all set to see a net increase in attraction count / capacity. That's good. (Please don't tell me you think losing Launch Bay for the door coaster is a lateral move.) I don't expect Disney to just blindly keep old things open in the interest of "not taking stuff away." Sometimes, things run their course.