generally what you’re talking about is proportional representation… systems like this tend to lead to a government comprised of a lot of minor parties, which sounds great!
but it has its down sides (and i’m not saying 2 party is much better, but it’s useful to be aware of the situations it creates): when there are a lot of minor parties with no clear “above 50%” majority, they have to form a coalition government and that can be extremely fragile
you can’t hold parties to election promises, because you just don’t know what they’re going to have to give up to form a coalition, and even if they do end up forming a coalition you really don’t know how stable that coalition is going to be!
i guess in the US there’s gridlock anyway, so what the hell right? may as well at least have gridlock with parties blocking legislation based on things you believe in… buuuuuuut that’s probably a bad example: first past the post is far more to blame in that case than proportional vs representative democracy
(fptp leads to extremism, ranked choice etc leads to moderation because people’s 2nd, 3rd, etc choice matters: you want to be likeable not just to your “base” but to everyone, because everyone’s vote has a chance of flowing through to you even if you’re not their first choice… if people hate you, you’re not going to get those preference votes when candidates get eliminated)
