If everyone who stayed home had voted for a third party that party would have won. Even if they split between two third parties, they would have sent a powerful message. Instead they made it clear they don't care. Now add in those who thought the major party was the only way to make a difference. BTW, if you votes for Harris you wouldn't have lost anything by voting third party and it would have sent a message to the Democrats.
If everyone who stayed home had voted for the same third party, it would have won. That's unlikely.
It's also unlikely that it would have been split between only two additional parties. In my state we had 5 parties on the ballot. Colorado (to pick one at random) had 12.
If there was any real movement to get non-voters to vote for a third party, there would likely be even more of them. As it is, each of those parties took a fair bit of effort to get on the ballot, knowing that at best they would "send a message".
If the message is "we don't like you", then the message has been received, for many years. But the reply is "OK, go get people to agree on somebody else", and that's the sticking point.
Oh, I looked. To my knowledge, Harris was the best choice even including third parties. Stein and West are both whackos and no one else even made it on enough ballots to win.
