The left have been in the business of dominating US court appointments since at least the 1960s. They realized that the courts offered opportunities for legal reforms that they were never going to achieve legislatively. Their efforts stopped short of SCOTUS only because of the Senate approval process. Because the Presidency and the Senate are often in the hands of opposite parties, SCOTUS is the MOST politically BALANCED court in the US.
This is, of course, delusional nonsense.
There is no solution to the problem that the courts are influenced by politics BECAUSE LAW IS POLITICS! It always was. It always will be.
This, however, is true.
The issue is, as with all politics, what kind of incentives do you build into place and what kind of culture around it do you nourish.
The Conservative movement - specifically the Federalist Society style - has decided to go all in with raw power as their approach, but seem very annoyed that people aren't pretending that isn't what they are doing.
The original courts merely presided in place of the King or the local nobles. They were never intended to be independent of politics. They were only intended as a dispute resolution mechanism that might result in less bloodshed (which even monarchs realized was disruptive to the economy, at least if it were to be widespread). Don't ask a system to do any more than it was designed to do.
If we got back to "dispute resolution system that resulted in less bloodshed" (because it was viewed as largely fair) that would be great.
Unfortunately, that's not the direction the right wing has chosen to go and I suspect it is going to get worse before any kind of truce to bring it back there is possible.