> When I upload photos to Instagram, I am not explicitly consenting to my photos being used for people's fetishes, even privately.
Well, they're in facebooks domain now, so you really don't have a tell in whats okay and what not after you uploaded them[0].
> but I still find it morally wrong and disturbing.
that's okay of course, but it obviously won't stop anyone from doing anything they deem okay and acceptable. How are the supposed to know what you find morally wrong and disturbing, anyways? For all they know those pictures are public and you want to present yourself to the world.
> legal to republish someone's public Instagram photos
According to the link that's instagrams business, not yours. If facebook doesn't care then there's not much you can do about it since you don't have royalities over the pictures in which you appear.
> But legal or not, I think it ought to be considered common decency not to post photos of someone on a fetish website without asking for their explicit permission to do so
Some people would consider "not poisoning the public water supplies forever" common human decency, but that doesn't stop multiple actors from doing so. "human decency" is not worth a penny on the internet, which is in my opinion common knowledge that we try to teach kids in primary school here. It does not matter what you think, since it's out of your hands you made your data public.
[0] https://www.dailymail.co.uk/sciencetech/article-2249952/Face...