Even in that case, there really isn’t much reason to vote for a third party. Especially if they’re one that only pops up on presidential elections while making zero effort to build an overall movement. There are some that probably are genuine, but I suspect most people willing to stand in a third-party presidential candidacy are likely either grifting or intentionally trying to act as a spoiler. Honestly, unless one of the major parties collapses or we actually somehow move past the first-past-the-post voting systems, third parties in general are just a waste of time and effort that could be used on something more effective. I honestly think that if you’re in a state where your vote in the presidential election doesn’t matter, writing in the name of someone like Bernie Sanders or leaving it blank would be a better use of a vote than a third party.
There are plenty of cis gay folks. “Straight” just doesn’t work if you’re trying to describe non-trans people.