I certainly understand and on some level of course agree with what you’re saying.
I do think the only way for another party to eventually move up is for people to not be afraid to vote with their conscious, and for whichever candidate they believe could do the job best - not for whichever one they believe has the best odds. Even if it started with local/state candidates, or if it took a few elections for more people to lose that fear of “throwing away” their votes after seeing increased numbers, I think that’s the only way that change could happen, and honestly maybe one of the few ways for the country to move away from the partisan gridlock it seems to be stuck in so often.
I have never personally felt like my vote didn’t matter, or felt guilty for voting for a third party candidate. I do my research on candidates, and vote for who I think is best, and that’s the best that I can do, aside from trying to encourage others to do the research and vote for who they believe is best.

People can talk numbers or strategies or whatever, but I don’t feel guilt for doing my best, nor do I try to make others feel guilty for voting the way they honestly think is best.
Like I said though, I’m aware my thoughts on more parties is likely just wishful thinking.