(queue up the two-party-system reply guys here)
I mean, that is the root of the problem. That and FPTP elections. It's just a mathematical reality that those combined guarantee third parties cause a spoiler effect.
Say you've got three parties. One wants to snuggle puppies, one wants to snuggle kittens, and the last wants to use both for target practice. If 66.6% divide their votes between the puppy and kitten snugglers, and 33.4% vote for target practice, the target practice party wins in our current system. That's just the mathematical reality.
We don't have to like it. Hell, we definitely shouldn't, and should push for ranked choice voting and similar changes. But it's a mistake to just ignore that that's the system we're currently stuck in.