My opinion: WDW sells nostalgia. Universal sells a theme park. The last few additions to WDW seemed to be more about keeping up with Universal than creating nostalgia. WDW needs to decide if they want to have 'just another theme park,' or go back to their roots of creating an experience. Long term, if they try to compete at Universal's game, WDW will lose. If they focus more on the guests, then WDW will win. That is how WDW has been able to stay on top while having rides and shows from the 70's. Just my opinion, but, one day, when I am CEO, that is what I'd do.
My opinion: WDW sells nostalgia. Universal sells a vacation.
Nostalgia will keep Disney in the lead, at least in attendance, for the foreseeable future. You need a generational view to even project a time when Universal would surpass Disney in Orlando attendance.
I went to Disney throughout the 70's. Then with my kids in the 90's. Even in the 90's, it required extreme planning to get close to your money's worth out of the trip. Running to specific rides in specific order, leave just after lunch. Pool and nap then return to park after dinner for kids rides. But Haunted Mansion alone carried enough nostalgia to make it all worth it - to me.
Our first split trip was in 1999 leaving Disney after 6 nights to spend 3 nights at the PBH. Those 3 days were the most fun, relaxing vacation we'd ever had. It made us realize our Disney trips were even more stressful than our normal lives and when we returned home, it was the first time we actually felt like we had had an actual vacation.
We made a deliberate decision to make Universal the nostalgic draw for our kids when they got older. None of us have been to Disney since 1999 (kids were 7-11). For 25 years we've been to Universal with them, and the subsequent grandkids, usually at least a single 9 night trip each year.
So for them, the nostalgia is with Universal, but it's vacation nostalgia. The draw is the resort, pools, rides on demand with no planning, etc. It's not just theme park based, and certainly not IP based, it's vacation based. Disney folks that take 1 or 2 days to blitzkrieg Universal are doing Universal like they have to do Disney and completely miss the advantage Universal has.
I don't think Disney will ever be able to create the same atmosphere unless it is isolated to a couple properties with unlimited
Lightning Lane. Sadly, my fear is that as Universal grows and begins to compete on Disney's scale, they will also find it difficult to maintain the experience that they currently offer.
Back to the point. If you told me I was going to Orlando tomorrow and could only ride one ride, what would it be? It would be Haunted Mansion, hands down. And 25 years later, I still rank ToT a top 5 ride in Orlando. Great ride, but it's the first "adult ride" I rode with my eldest when she hit 40 inches.
Nostalgia is a powerful thing and it will be at least a generation before Universal could come close to knocking Disney off the top spot.