Have you ever been on RSR? It feels and looks NOTHING like Test Track. There are multiple spinner rides and Dark Rides and Boat Rides and Roller Coasters and at no time does anyone say...Gee, Pirates Of The Caribbean is exactly like Small World... Or What a shame Buzz Lightyear and Haunted Mansion are so similar...I cant tell them apart!
I hate that argument that they cannot use one technology because there is a ride that uses the same system within the 4 theme parks. Let's put that argument to bed...
Yes, I've been on RSR. Yes, I agree it's nothing like Test Track in feel. It's a masterpiece. Test Track is something I go on because it's mildly entertaining. But the layout is similar and obviously the ride vehicles and general functionality are similar. Also, I've heard the exact same thing said about Indy - that Disney wouldn't put Indy into WDW because they already have Dinosaur, which looks and feels nothing like Indy and is a much poorer attraction.
For many rides, the operating system doesn't matter, but for some, people do notice. Would people care if Rat was an old-school omnimover vs. a trackless ride? I don't know. I haven't riden it. I understand that you have, so perhaps you have an opinion. I get the impression that people would ride it for the ambiance, story, and IP. Personally I don't think the ride system matters as much for that type of ride. For RSR/RR, to an outsider - the casual guest - they appear quite similar. If RSR was built at WDW, I feel like those casual guests might not waste their time waiting in the (stupidly long) line for Test Track knowing that RSR is a far superior experience. And if interest/satisfaction in Test Track goes down, that's bad for Epcot.
The Cars rides are better overall than TSL and that Carsland is a better land overall than TSL. It's not even close. Yes, they could've decided the IP fit (and they did by inserting the Racing Academy which we quite enjoyed, I'm sure others have their own opinions). But for a park that is supposed to celebrate the best movies in history, Cars is not as important as the Toy Story franchise. (And they already had TSMM in place to feed into the TSL.)
Should Disney have kept TSMM, added RSR, and then added some other rides from other Pixar movies? Maybe. I was just putting a guess out there as to part of why Disney went with TSL and not a Carsland clone (which is its own ball of wax). I'm sure the insiders know much better than I do how and why TSL came to be.
Also, for anyone who hasn't been on RSR, there's a side-by-side video with Test Track on youtube:
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