That's simply not likely. 75 million voters went for Trump in 2020. That's almost half the voters. It's unlikely that there's 75 million voters out there that are not Democrats or Trump supporters. If that is the case, Bidens support should either have been higher or there should have been at least that many blank ballots, or alternatively, Bidens 80 million votes is half Democrats and half anti Trump Republicans, in which case, the Democratic party, which historically is the larger party, is all but dead
The USofA has antiquated First-past-the-post system; this is largely how a system founded by people opposed to party politics spiralled into a two party non representative bog hole.
Being opposed to MAGA and simply not supporting MAGA doesn't make a voter pro-Democratic Party nor does it mean they want to waste their vote on a minor Libertarian or other third party with the result that Democrats win.
The US electoral system fosters the stupidity that results .. the still Republican anti-MAGA are (mostly) afraid to vote Democrat, minority parties aren't viable, and popular opinion and public support for various policy is never reflected in legislation.
If the US had a better electoral system it'd see better outcomes.
The fact the you would bring up
Liz Cheney pretty much invalidates any opinion you might have of the Republican Party. There’s a reason that disgusting and vile thing is now “teaching” at a radical left wing training school.
There's support for Liz Cheney, a former chair of the House Republican Conference, coming out against Trump et al.
Are you sure "anti-Republican" is what you're seeing and not just calling out the MAGA faction for their behaviour?