If the DNC wanted to, it could pass ballot & electoral reform. It doesn’t, because FPTP/winner takes all benefits them doubly - either they lose and can fundraise off “red team bad” messaging, or they win power and get their turn at the levers of power.
If you’re politically homeless on the right, anything even slightly to the right of median is preferential to ‘conserve’ the world you’re clutching to. Slowing or preventing change is your mantra politically, because you like the status quo today/previously
If you’re politically homeless on the left, you’re bullied in liberal unity under big-tent centrism, even though it’ll never effectively serve your core interests like right wing unity would. There may be some overlap, but good luck with actual legislative movement on LGBTQ+, unionization, campaign finance reform, alternative policing, etc
Under a different system we’d actually have coalitions and better representation on issues- especially topics with entrenched left-right collusion like foreign policy.