What do players even do during ERP ?

[Xelanar]

Oh they do.
Eventually when they figure out that the person behind the Fem Miqo/Au is a huge catfish.

I don't think many people care about how the other person looks, when reading their smut.
I guess it's not much different than reading a steamy novel - it does not matter how the author looks, right? It's all about the novel's characters, and the same might be true for eRP.