[Astromancer]

Bioroids are controversial in wealthy areas like the EU and accepted in poorer areas like the Caliphate. Thus those who could make vast numbers of them don't, and those who'd want to make vast numbers of them can't. So numbers stay down.

If there was a general belief that bioroids aren't real people, just simulations, they'd be more common. If there was a general belief that bioroids were fully human/sophant no one would want them.