The carnie rides at MK didn't originally have an entire land dedicated to them like the super concentrated Toy Story Playland, Dinorama etc. Instead rides like the spinners were scattered sparsely and individually around the parks, not taking up large plots of land with their presence (heck Astro Orbitor is even built on top of the Peoplemover loading area, taking up even less space than others). Their presence doesn't dominate the park, or even a particular area/land (prior to Dumbo moving over next to Barnstormer anyways).
The problem is discerning whether the carnie rides are going to heavily eat into the budget, and how many there are. Besides Toy Story Playland, even the other lands could be dominated by carnival rides. Something like an X-wing spinner for Star Wars or the lesser attractions from Cars Land (or worse, the awful Cars ride they built at Paris) just for examples.
From what Spirit said, it sounds a bit worrisome given that the carnival rides are all he commented on regarding whatever info he has obtained. As a Disney fan, I think he'd be at least hint at something positive if he had heard something.