To me, this is all summed up by the fact that people think golf should be fair, which really just means easy for them. If this was an island green, it would be the "signature hole" on the course, and everyone would be touting it and showing pictures to all who haven't seen it.
Water is way more penal than sand, right?
I also disagree about the "double penalty". Having water with a tree in it provides an aerial hazard and a ground hazard in the same spot. Is that worse than if both were presented in separate locations? Either way, they are hazards to be avoided. It could be argued that they are easier when put together because you can avoid both at the same time.