But even if a party gets, say, 5% of the vote and gets funding, that level of vote splitting can influence who gets a seat now. That might be fine and dandy when the short term doesn’t matter too much, but right now, the stakes are very high in the US, since the right straight up wants to dismantle democracy, kill trans people, and completely ban abortions.

Those are high stakes just to likely get some more funding for a third party (much less win even a single seat).

IMO any political pressure that could go towards pushing third parties should first to towards electoral reform. Only then can third parties be voted for without putting a lot of people at risk.