Like all meaningful change, you have to convince enough people to get involved and to do so more often and consistently than every four years at the Presidential general election. It's this belief that the change is going to come from the parties that is the core problem. Everyone complains about having to vote for the lesser of two evils, but then they do it and go back to sleep for another four years. At best, they just gripe about the government never acknowledging that they are responsible.

It's also not like local or even state level RCV would realistically be sufficient for these whole sets of overarching problems that the US struggles with. You're not locally voting for RCV and then gaining the ability to vote for a party that will actually give you healthcare, will connect your city with others via rail to help rework infrastructure, will solve your housing problems and your homelessness, and they probably won't be solving unemployment. You can maybe vaguely hope that the existence of such a party would put pressure on the federal government to ask "why can't you do this", but that would only happen at the state level with one of the states that actually matter, like california or new york or texas, and good luck getting any of those places to go in for RCV considering how strangleheld they are.

The most you could hope RCV to improve is maybe to make it so you can get someone that's willing to make your ISP give you free shit, or establish a free ISP, and also maybe to give your town a bunch of roundabouts, and maybe approve some missing middle housing which will probably skyrocket housing prices in the surrounding areas since it won't really be doing anything to solve the problem at a national level. Which isn't nothing, right, but that's kinda boof.

Then we vote them out