Populism isn’t fascism, but neither is democracy. In general, political systems that are set to make stronger governments, either with a second vote or tuned to just have two parties, makes that the parties don’t represent accurately the people.

This makes that people vote against what they fear and not for what they believe.

Democratic decisions should be done by consensus, by negotiating with each point of view trying to get to a compromise or a middle ground.

On top of this, if you have more parties being part of the government in a coalition, corruption is harder since the parties watch each other.

Humans are diverse and can enrich with collaboration and common wealth. Having two parties, one that say that slaves should be exploted and another one saying that slaves should have some rights, does not represent the slaves points of view and their experience on handling things.