I think this is an interesting point. If there wasn't already so much screenz, would this ride rate better?
I haven't had the chance to ride yet, but I'd think so, at least in terms of how it was executed. Transformers is a pretty good ride in a vacuum, but being able to point out exactly which parts were directly lifted from Spider-Man on one's very first ride definitely knocks it down a few pegs, and for those who end up riding Transformers first, it knocks some of the wind out of Spider-Man because the novelty is lost.
If Fallon is as cut-and-paste in relation to Despicable Me and Simpsons, I think that's going to knock it down as well, and it could end up hurting the previous rides in terms of guest satisfaction for first time guests if it is recieved well(why is Simpsons still here? It's just a dated version of the Jimmy Fallon ride).
I don't truly think there is screen fatigue, nor do I think reusing a ride system is inherently a bad thing. I think there is a fatigue from seeing the same three screen-based tricks. If I ride Spider-Man, I don't feel like I need to hit Transformers. It's the same way with Despicable Me and Simpsons, because they are nearly the same ride in many aspects. Much of Universal is beginning to feel like you can do half the park and get the full experience. This is really bad, especially when you are dealing with a company that *can* make compelling, unique attractions from the same ride system (MiB and Cat In The Hat, Gringotts and Mummy).
Going slightly off-topic, I think this is why there doesn't seem to be as much of a concern over Disney having two screen-heavy rides in Avatar Land, because Disney consistently proves that their use of screens does not mean that the rides will feel like modified copies of previous attractions. Universal has lost that trust from its consumer base, and seems unlikely to start winning it back until the next decade.