America has had two parties for most of its existence. Each party usually had its more moderate and more extreme group. Most of America was more moderate, at least in the last half of the 20th Century. Then the Republicans began to play the All-or-Nothing game. No compromise, no negotiations. The Hastert Rule, The McConnell Block.
The Dems right now have two strong branches in Congress. Most of the bigger cities are sending more progressive people to Congress. The Republicans are a mess of Trump and anti-Trump.
Third parties have been effective in America and creating new ideas and slowly having them adopted by a major party.
If there were three major, established parties, there would always be minority rule. We would have to get rid of the Electoral College in Presidential elections, or else the House would vote in the President.
You want a lot of parties? Look at how well it’s working in Israel.
What we need is politicians who negotiate and compromise. We have a bunch of ideologues, many of whom have been corrupted by big money. We have to get money out of elections. We have to make voting possible for everyone. People need to pay attention.