Liberals and conservatives have fundamentally different values and cognitive systems. They’re not just randomly assigned teams. Part of the conservative way of thinking emphasizes in-groups vs out-groups, tribalism, adherence to hierarchy. This is what has allowed them to achieve extreme partisanship - they advocate/defend anything their side does, and attack anything the other side does. This has been cultivated and reinforced by decades of propaganda designed to lie, stir up outrage, and increase tribalism as part of a “culture war.”
Liberals are much less beholden to their tribal identity, they are much more likely to think about each issue on its own merits and not just always go with their group no matter what. A human shitstain like Trump can get 90%+ approval from Republicans because of this factor, whereas any Democrat that was even a quarter as awful a human being as Trump would be dumped in two seconds.
This also allows republicans to act in lockstep even against the interests of their voters. They’ve cultivated and enhanced the tribalism to the point where their poor white supporters will cut off their own noses if they think it will hurt their enemies just a little bit more. Cut off their own food stamps, refuse medicaid expansion, etc.
This means the GOP can do anything they want completely disconnected from the values or interests of their voters and still receive complete support. This means they have essentially complete party discipline and no attachment to the actual wishes of their voter base.
In comparison, democrats need to try to appeal to their people through reason, policy, etc. There’s no “my team, right or wrong” on the democrats. Most people who are democrats probably kind of hate the democratic party and definitely don’t feel like they owe them loyalty or anything like that.
That, as well as their lack of good faith, is the basis of most of the GOP “outmanuevering” the democrats. I am as critical of the ineptness of the democratic party as anyone in the world, but it’s hard to overcome a disadvantage like that. Imagine the freedom you have for political maneuvers where you don’t have to worry about the conflicts between your different bases (like how the religious right, rich people, and poor whites have very little in common), you don’t have to worry about actually delivering on any policy that helps your base, you don’t have to have character or decency, you don’t have to have rational consistency, you don’t even have to act in good faith or in the best interest in the country. All you need to do is convince people that they need to support your in-group no matter what, and hate the out-group no matter what, and you have complete and total support.
It is extremely difficult for good-faith actors actually trying to enact rational policies and manage non-cultist individuals with different values and policy desires against that unbreachable wall of tribalism with the way our political system is structured.