Until the Electoral College is abolished, third parties will never gain enough momentum to make a positive difference. All they do, currently, is siphon votes away from the ideologically closest party. If not abolition of the EC, then at least nationwide ranked-choice voting is a minimum requirement.
If 3rd parties really want to make a difference, instead of trotting out every 4 years for a presidential run (cough Jill Stein cough), run as independent or 3rd party in lower-level elections and work toward systematic change from the bottom up.
If a 3rd party only pops up for the big-ticket elections (cough Jill Stein cough), then as far as I'm concerned, they're spoilers acting in bad faith.
AFAIK, that cough is not COVID; it's just really dry in here.