You should be voting for people because they generally share your views, yes, but more importantly because they're willing and able to become experts in the things you need to be an expert in in order to be an effective lawmaker.
I have actually come to disagree with this sentiment. Look at what we have right now in the US: pretty much complete gridlock when it isn't just partisan curb-stomping. No one is willing to compromise, no one wants to discuss things rationally. Everyone goes in with their answer and attempts to beat others into accepting it and it's our fault, as voters, because it's what we ask of them, because we keep being told that we should vote for people who share our opinions.
I think we should vote for people not because they share our views, which are likely based in ignorance, but because they demonstrate the ability to make informed decisions and come to reasonable compromises. Look for the ones who think things through, who are willing to admit they made a mistake, and who will change their opinion in light of new information.
If we continue to vote for people without these qualities, our elected officials will continue to lack them.
We're at a gridlock because a significant portion of this country is woefully misinformed about just about everything and are puppets to an incredible machine of profit and no-holds-barred capitalism.
You have no one to blame but yourself if you refuse to even try.
I like this model, but I think the rub is that rubric itself expresses a view that not everyone shares. It pushes the problem back one step, the disagreements become meta.
Any interest group can defect from the prisoner's dilemma where we all vote for tabula rasa rationalists, and instead choose the strategy of electing someone who pledges unwavering support.
They'd likely disagree with you that they don't know their interests and that they would be better off with smart generalists. And once some interest groups are getting unwavering support, then my bet is that strategy cannibalizes the "rationalist" strategy completely before long.
I'm not endorsing that outcome, I just think that's how things fall apart, and it's hard or impossible to create systems that prevent it.
Tyranny of the majority is incredibly tough. It's basically a sheep/goats problem, where you want majoritarian common sense to get through, but majoritarian selfishness to be stopped at the gate.
Federalism seems the best hedge against it so far, though even that seems to vary wildly in effectiveness. (e.g., Sometimes Jackson ignores Marshall.)
One way might end badly, but the other certainly will.
Malcolm X's speech about the ballot and the bullet is worth hearing. Maybe democracy is only partly about rational policymaking, and mostly a pressure valve to prevent violent revolutions.
That's not to dismiss it, avoiding violent revolutions, even partly, is still a massive benefit for humanity that's hard to overrate.
Did you not watch the latest Zuckerberg deposition? Most of our officials do not care about becoming experts in anything. They're old, tired, and ignorant and they are mostly concerned with maintaining power, not learning new material.