It’s all a matter of perspective.
For several years I was a member of a women-only BDSM club in Boston. As the oldest person there but the least experienced I was more of a voyeur than a practitioner, but I had friends there, and made some more, some of whom wrote for my early anthologies. I learned a great deal, enough to understand mind sets that I didn’t personally share. We had monthly meetings with demonstrations of skills, and the occasional play party, especially the yearly one at the Fetish Fair Flea Market (which moved from hotel to motel over the years as locals discovered our transgression of their taboos and overrode the pleas of the hotel or motel owners who loved the business we brought.)
But we had our own taboos. Whips, floggers, spanking, blindfolds, swings, dominance, humiliation, submission, slavery, pony girls, intricate rope bindings, even needle play--those were all fine, as long as they were done according to safety rules. Our taboos were things like penetration without nitrile gloves (or similar barriers,) blood play without disinfectant for both body and tools, and, above all, nonconsensual contact. Oral-on-genital play without dental dams was in theory taboo, but generally overlooked.
Would people have had more fun without taking into account safety measures? Probably not. Just knowing that what they were doing was considered taboo in “mainstream” society was fun enough. Did those in charge of enforcing safety measures get a charge out of wielding that power? I’m pretty sure some did. Whether enforcing taboos or breaking them is the most fun depends on the individual personality and perspective. I do know that the enforcement-prone folks were those most involved in having never-ending revisions of the club bylaws, and elections of officers, and after quite a few years those who just wanted a good time drifted away. The online evolution of the Fetlife website had something to do with it, too. In any case, that club is no more. There are still some functioning “dungeons” around, and the Fetish Flea Market is still popular, but the people I knew there have moved on with their lives (aka grown older, although never, of course, catching up with me.)
In an historical context, defining what’s taboo has varied from era to era and culture to culture. In some cultures menstruating women were taboo and had to retreat to separate huts or tents for about a week each month. That would be an “ick” factor taboo. Food taboos may have been based originally on observed dangers, like poisoning by spoiled shellfish or trichinosis from uncooked pork. The incest taboo is more complicated. Observation may have shown that inbreeding tends to produce less healthy offspring, but that didn’t keep Egyptian royalty from preferring to keep it all in the family. In these modern times with relatively available means of birth control incest shouldn’t matter that much, except that it does when the power differential is extreme, as with father/young daughter intercourse, and birth control tends to be forgotten in those circumstances.
Do animals other than humans have sexual taboos? My impression is that most mammals mate only when the female is in heat and therefore receptive. And for many animals, especially herd animals with one dominant male “owning” all the females, incest is no consideration at all. Animals other than primates don’t seem to have the complex sex-associated activities like bondage or whips that the members of clubs like the one I knew enjoy partly because they’re considered taboo. Sure, our hands with opposable thumbs have a great deal to do with it, but to animals the sex itself seems like enough. Do animals, in fact, take pleasure in doing what they know is forbidden just because it’s forbidden? Okay, maybe cats do, but how can we know for sure?
Humans, though, seem to have a need for taboos, whether they obey them, enforce them, or get their rocks off by breaking them. It’s not entirely a matter of sex. For instance, I know perfectly well that my title for this post ignores a grammatical taboo. As the object of the preposition “to,” I should have said “whom,” not “who.” But it sounds better the way it is, so grammatical taboos be damned.