Privately owned does not mean that there is a reasonable expectation of privacy
on a common area open rooftop pool, open to anyone staying at the hotel and their guests. There is nothing private
about the open hotel pool rooftop with helicopters and other taller hotel roof top pools and hotel rooms of adjoining taller buildings all overlooking it. It's a public hotel pool on an open roof top. The airspace above it is also public.
There is not always
expectation of privacy. There is none in this case. It has to be a reasonable expectation
, and there is none at a public hotel pool open to all hotel guests and the visiting public.
Choose any definition you want of voyeurism. This does not qualify for all the reasons specified above.
Google Earth is infamous for having captured even nude sunbathers on rooftops. While they blur any such reported images, they also do so for all faces in public as well.
Sunbathing on any open hotel rooftop poolside does not have a reasonable
expectation of privacy, any more than at a public beach. The subjects are not nude sunbathing. They are all wearing bathing suits. They are not engaged in sexual activity. There is nothing private about sunbathing openly, and their activity does not suggest they have even an unreasonable
expectation of privacy. They are openly waving at the drone, if he was being serious. If so, they are welcoming the attention.
The sunbathers need not approve or consent to being photographed by anyone who chooses to do so, any more than a person in public being photographed. Photographers do not need a person's permission to photograph them in public. It is polite and good form to ask, but never required.
of street photography can be debated, but it is still legal. This is no different. I am merely pointing out that it is not illegal, and is not voyeurism by any definition, whether you approve of it or not.
I am not taking a position on its morality, only its legality.
It still has not even been established whether the OP was kidding or serious. I suspect the former, so this is a purely academic discussion! If you want to delve into it deeper, here is a link that covers most of the issues.