It’s such a cool idea, I can’t wait to see it happen.
Luckily capitalism is too unstable and self-limiting to lead to galactic god-emperors. We’re a long way from that kinda tech, if it’s even possible given our material conditions, and it certainly won’t be capitalism that squeezes through that great filter
I’m not sure I agree with the idea that capitalism can’t achieve spacefaring civilisations. They’ll be horrible and bloody civilisations wracked by regular collapses, but IMO the same forces that kept the Cold War cold could help the capitalists manage this. Obviously mass death or even species extinction are horribly likely scenarios for such polities (and for our own) but they’re not inevitable. We might actually get unstable space opera/cyberpunk dystopias!
When I look at capitalism, I see ‘systemic collapse due to internal contradictions’ or ‘self-limitation via ecological destruction’ before I see ‘limps into space’ but, I agree, there’s certainly no way to know with certainty!
For all we know, my descendants could be space-serfs, working their asses off in the soylent space factory to earn enough for their daily air subscription!