You guys really don't get that your voting system only leads to two parties. As soon as one of those parties splits up, the other one will literally always win, that's just a mathematical reality.
It is true that both of these two parties are terrible. However, D is slightly less terrible as R. If you stop voting for D and go for X which is theoretically objectively better, R will always win. So a vote for X is effectively a vote for R.
Yes, if suddenly all D voters would move to X, then X would win. But this is simply not realistic. The only realistic way for change is for the slightly better party of the two to always win, which would make R die out. Then a farther left party will emerge, that might even want to change to ranked choice voting. If not, the whole spiel has to be repeated until D dies out because of never winning.
This is incredibly slow, but slow is how our society changes. Even the French revolution didn't just suddenly happen, hundreds of years of starting to understand how terrible monarchy was and building the knowledge of alternate systems among the general populace was required. The real change is people gaining more knowledge, gaining a better understanding of reality, themselves.