An issue with gangbangs would be the huge amounts of extra work, especially if each combination has a unique animation (like in one of the GOATs, Parasite in City).
It's the reason why a lot of games that do have that kind of thing tend to opt for the character to be in a base pose and then animate the other...participants around that. Personally, I wouldn't be interested in that, and the work put into that could just go into more actual unique animations instead.