If your implications are that the popular attractions are "thrill rides" means that thrill rides aren't very thrilling. Disney has gone to the edge of the envelope making rides that seem thrilling, but are not at all what everyone else has in mind. What they have and to the limit that they have done it, should be the extreme that one would ever find there.
But for the sake of argument lets look at the popular attractions are...
MK... The three mountains. Space, Splash and Big Thunder. Kid rides in a thrill ride park.
Epcot... Soarin... heart stopper, that one.
Mission: Space... somewhat intense (orange) but thrill ride? Don't see it.
Test Track... Wow, 65 miles an hour for about 12 seconds. I went faster then that on the access road coming into WDW.
DHS... RcRC and ToT. I'll give you those two, but even then unless they are out in the open air, reduced thrill.
DAK... Dead Yeti Mountain... OK, but mild by comparison. Dinosaur... Yawn!
Now by my description it would almost sound like a Disney negative. It is not, that is how Disney should be. On the edge but not over it.
Many of those things are "popular" within a specific grouping. If you have 10 attractions and 1000 people per day and one of those attractions is a "thrill ride", one may see 200 people per day at that ride. However, 800 people found the others overall more popular. A theme park is not an individual ride it is a combination of many, but, it must stay with it's target grouping to be able know what to plan and what it should be. It would be tempting to look at the individual attraction and think ...wow... look how many people went to that one. If we had 10 of those we would have had 2000 people here. That, isn't how it works, however, and in the meantime you have changed your entire mission.