That’s just what has happened on Earth, though. Also I didn’t specify they’d be coming to us - if they landed here in something we’d recognize as a rocket, then I’d suspect we’d have a lot more in common with them.

But what if they evolved in gas clouds? Or hell what if they perceive higher dimensions? What if it’s a 4D being, capable of instantaneous long distance travel through spacetime - they don’t need math for that. Or even language. Those are far-out scenarios, but I’m just saying that it takes a very earth-centric, anthropocentric view of intelligent life to assume the sorts of things that’d make communication possible.