I understand that line of thinking, and you'd have a point if the senate could act alone. But the senate and the house have to agree on everything they pass, with very few exceptions. That means that the fact that Rhode Island gets an equal vote in the senate doesn't actually matter if the majority of the population doesn't want something anyway. In the same way that the majority population doesn't matter if the individual governments can't agree.

The people in Rhode Island don't matter as much as the people in California for sheer numbers, and that is already reflected in the house. Seeking to abolish the senate isn't an exercise in majority rule, it's just disenfranchising the minorities that exist.

Edit to directly answer your question:

Should we care about the states or the people in the states?

We should care about both, given that we are a nation comprised of 51 smaller governments. It's asinine to assert that those governments don't matter on the federal scale. We have a system established already that cares about both. Axing the part of that system that keeps the most populous areas from getting everything they want is not the solution you think it is.