> But if a person votes for bad people and bad policies...
The entire point of voting is that you are allowed to vote for whoever is running. Of course, the notion of a "bad policy" is as old as voting itself, but the noblest democracies are those which don't judge people for voting as they see fit, or else what's the point of voting at all? Just appoint a righteous elite to do all the political appointments for you.
However, just as there's been no consistently wise electorate, neither has there been a consistently wise elite class. In the end, in both cases, the best you can do politically is build a bulwark against corruption because you can't avoid it, which is why the stablest governments are the ones that make the job of the highest political seats as difficult as possible to actually do anything and put the bulk of the power in the hands of committees that have to argue about things to come to a decision.
> And so, if voting is good, maybe we should have more voting.
Voting on its own is not inherently good. Plenty of dictatorships operate under the guise of voting, where either candidates opposing the ruling party are entirely absent or voting for them is punishable in various ways (which is why the political polarization in the west is particularly chilling). There are plenty of "People's republics" out there that are neither republics nor representative of the people (unless, perhaps, you narrowly define "people", as the US originally did).
What is arguably good (at least in the liberal western mind) is maintaining a system of political friction (checks and balances) that ensure different parts of the government are effective limiters on each other's authority to make it as difficult as possible for a tyrant to seize control. IMO Trump was a pretty solid litmus test of the resilience of the American government against tyrannical takeover.
The downside of this, as we're seeing the recent competition between east and west, is that tyranny can be much more effective at getting stuff done than democracy can hope to be, at least in the short term. However, strong tyrants still die and eventually a weak tyrant takes their place and the country falls apart.
The (theoretical) strength of representative government is that it outlives any one or handful of strong rulers. I say theoretical because technically ancient Egypt's history spans more years than the entirety of human history after Christ (so far), but as can be seen in their history, they had plenty of royal family squabbles and foreign invasions in that time. How they retained national cohesion through it all would be an interesting study.