I like that too, though it's not as fun for societal corruption and stuff like "Horde dominance" if it's essentially an equal action society.>>40366620
Rexx got blasted because some weirdo who saw Jaina as his precious, pure waifu got pissed that he made porn animations with her and spam submitted tickets until some poor customer support person went "fucking hell alright I'll inform legal" and they sent him a C&D. He made a whole manifesto about why he did it after it happened, Blizzard didn't actively seek out a ban on him.
I think the real reason they don't touch it is because it can be kind of weird. Garona was essentially implied to be the result of rape for a while, and if you introduce genuine halfbreeds you have to then consider how society views those halfbreeds which can lead to cringe territory real quick. The other issue is that they need their own models which adds extra dev time. There's a reason a lot of other settings go with "They can't" or "They inherit the race of their mother besides minor elements" as their lore.