Earlier quoted context omitted.
It is useful for signalling. It is meaningless on the actual election outcome. If everyone disenfranchised voted for people they thought were good but unlikely to win, you'd maybe get enough of a signal to change the party line in future elections. But that's incredibly hard and similarly meaningless at small scale. Getting people to vote for first order effects is difficult. Try getting them to vote for second order…
Voting is not about winning.
2) I've pretty clearly addressed that the are secondary components to voting like signalling your view. These views are largely ignored by the political process at the presidential level.