system
Given the following post, respond as if you're commenting on Reddit:
human
[Black Mirror] Why would sex be coded into a street fighter-esque game?

Seriously though, do age-rating bodies no longer exist? If they do, does this age-rate the game as 18+, as it is essentially a form of porngraphy? Why would you put sex in when it blocks out millions of potential buyers who are under the age of consent?
gpt
A pretty fundamental aspect of modern game development is asset re-use. Presumably at some point, a feature-complete avatar system was created and distributed for developers to use in their VR experiences. (consistency is important for immersion, imagine if your hands "felt" different in every game) Each developer extends said template for their own uses, adding features like "falcon punch" on top of the existing ones. As for why this template can replicate a sexual experience, well, why not? 

As for age limitations, we don't know if kids are even allowed to use the VR hardware, so that may not be an issue. Alternatively, there could simply be limitations put on children's avatars. This is a good workaround for the age-rating/blocking you brought up. Children simply aren't physically capable of the same things as adults in virtual spaces. (Think Ken doll anatomy)