Reddit still has those subs about beating women and lynching black people, right? Get over yourself, voat is better than every single example you listed.
I think stackexchange are still running on IIS so it's probably close to doable - although I imagine they have some seriously smart people and resources way beyond what Voat will in the near future.
That said, does Azure play nicely with IIS? I bet it's expensive but can you scale that way maybe?
I thought the super secret internet clubs era was over. How old are you? Most people on voat cross browse. There's even a plugin to put both aggregators in the same page. I don't get where this idea that voat is that "den of pedos and fat haters" is coming from.