You're making the implicit assumption that more of those people exist than the rural and suburban types, in which case... Yes? Your comment cuts both ways - one of those groups is going to be the dominant culture and if your argument is that the smaller one should win, I don't see the reasoning to back it up.

The electoral college moderates the effect. The big states still dominate. Just not as completely. The small states have their voice instead of being completely irrelevant. It's not that they "win" or even have an equal say.

You've assumed that everyone agreed at some point on majoritarianism, which never happened.

The coastal city culture is already dominant in all types of media and academia and large corporations.

It's not about winning. The original motivation for the US's structure is to impede lawmaking at the highest levels unless absolutely necessary. Making laws is not making progress.

> The country was deliberately designed as a collection of independent states,

Hmm... Couldn't it be argued that this haven't really been the case since the civil war?

When I lived in SF, most Americans I met weren't originally from California (not had they lived there long).