I think there’s a more likely scenario #4 here…
#4 Disney is waiting because they can.
I’m not judging whether its the correct strategy either way, but its clear that Disney knows they have wiggle room built into the market. The can let Universal invest significantly, while they work on infrastructure, efficiency, and DVC while still making positive gains each year. It seems Disney is doing the bare minimum investment in attractions as long as they can get away with it and will react more substantially if and only if they see their numbers dwindle.
I don’t like this strategy personally because it means less development for the parks. But you would have to admit, Disney is being proven right to the extent that regardless of spending, the numbers continue to grow. Unfortunately, reactionary spending may be too little too late by the time it starts to affect revenue and attendance figures and it may take them longer than they think to win back that market share if they let if get to that point.