While all of that is true, not all of those 360 rooms are options for you. Hotels aren't like cruise ships where everyone arrives and departs at the same time. On any given day, only a fraction of the rooms are being vacated. If 20% of guests were departing on your arrival day, that's about 70 options for your room assignment. And at PVB, those 70 rooms are spread over 2 different views (Standard / Preferred), 3 buildings and 3 floors in each building. Some of the rooms are undoubtedly the same view + building + floor, but if they aren't right next door to each other, they don't meet your request.
If it took that much effort for the front desk to assign you to connecting rooms, It's very possible that they did not have enough open pairs to meet all of those requests, and subsequently took the connecting rooms away from another party.
There's more to it than simply believing it should be an easy request because there are so many room options available. In reality, only a fraction of those rooms are options on any given day. Room assignments are very challenging, especially at Walt Disney World where there's so much information available about room locations and views, and a lot of guests requesting the same things.