Just wanted to toss in Star Voting as an alternative I was just informed about yesterday. Seems to be more RCV than RCV.

In order to maintain ballot status and to run as third party candidates at lower levels, they actually have to run at the presidential level in many states. They're forced to run a presidential candidate and split the vote, or else they're locked out of many states.

Then run in local elections and fight for ranked choice voting

Will never work. The second a third party starts gaining traction, both the DNC and GOP collaborate against them. Ranked choice voting isn't sufficient either, and even if it was, the DNC and GOP will only allow minor implementations at local levels to make it seem like voting works, and will toss the football back and forth forever. It will not work.

instead of only running sybolic national campaigns that only serve to spoil the left-leaning vote...

There is no left-leaning party other than the Greens and PSL in this election. Reform is impossible, only revolution can actually implement leftist change, which is why PSL even participates to begin with. It's to tear the curtains back and show the kabuki theatre for what it is.