In the warmer summer months, I somehow doubt that Disney is able to refrigerate the pool water to your preferred level of coolness. With the ambient temps and relative humidity so consistently high in the summer, it would take some kind of very expensive Disney magic to keep the pools from warming up.
I thought the pools were only heated to 80º? But I'm with you, the pool water is too hot in the summer. I bet the pool water gets warmer than that just because of the air temps.
The sun and the high summer temps make it hard to cool the pool down. We have a pool in our back yard and last year when we were having some really hot streaks our pool easily hit 90 degrees and it wasn't refreshing anymore. The only thing I could do is drain some water out every night and put some fresh cold water in and it took several days of doing this to get the temp to drop. Oh and I do not have a heater for my pool it is all heated by natural sunlight. Some things are just out of people's control. I'm sure they could add some coolers and while filtering the water it could filter through there but I'm sure that would be quite pricey.
IMO a warm pool is better than no pool!!!
In response, I'll say that we have a pool in OHIO. NE Ohio, to be precise. So, far we haven't opened it, the weather has been crap. Last June it was almost 100 at this time, but we've been inundated with storms. We don't use a heater, only a solar cover. Mid July, the solar cover isn't needed in a normal summer. It runs around 85-90. When it gets close to 90, it's like taking a bath, not as refreshing.
It would've never dawned on me that Disney heats their pools past June. Obviously, being from the North, we went swimming in December (it was heated, yes) but we thought the weather was beautiful. Heck, I wear shorts when it hits 60. Everyone is different.
I will allege that the quantities of water needed to cool the pools in the equatorial heat of Florida summers would not be cost effective, but I get that it can be icky to swim in. There's enough chlorine to kill a cat, so I wouldn't worry about the germ issue...hot tubs, that's another story!
People vent, that's life. There's way worse venting going on this board than this thread...check out line cutting, kids too big for strollers, etc...

Peace!