Earlier quoted context omitted.
One of the reasons the US has a divided Congress is to induce gridlock. This was a design goal. Remember, government is other people making rules for you . The more efficient they are at changing the rules, the riskier it is for you to do just about anything. The more efficient they are at changing the rules, the more likely they'll take an extreme position on a contentious subject.
But this is why a two-party system can be a liability. You artificially create an us-vs-them scenario, with the other side as the enemy, and any agreement with them on the issues is capitulation. As a result, you end up with a scenario in which there is always one side with a majority, who are capable of doing whatever they like, and one side with a minority, who are left to scrabble for democratic scraps, pushing bi…
But that's not what I'm talking about. What I'm talking about is the divide between the Senate (2 senators per state) and the House of Representatives (based on population), and the inclusion of techniques like the filibuster. It's harder for one party to get a majority in both House and Senate than it would be to just get a majority in a single parliament. It's even harder to get supermajorities in both. It's even harder to also get a friendly president at the same time as all of those other things. This means that there's almost never a time when one party can just ram through its whole agenda. There's almost always gridlock.
From what I've seen of single-house multi-party systems (like parliamentary democracies) there's a lot more compromise, which is a good thing, but there's also a lot less gridlock, and that's a bad thing.
It's actually a good thing that successful bills tend to be either issues the vast majority of the country agrees on, or else very watered down.