Not at all. It's very obvious that the voting population will vote for one or the other....even if they hold their nose to do so.
A third party candidate hasn't been a viable option EVER, that I remember. Even less so for a write-in.
So, if voters are going to vote one way or the other, and it's a close race, then every person that DOESN'T vote is actually giving a one-vote advantage to the candidate they wouldn't have voted for, had they chosen to hold their nose and vote.
I mean, come on.... the two candidates are not even CLOSE in ideology... it's the details that turn voters off.
The only way that YOUR scenario happens (no impact on the election) would be for every potential Trump supporter who decides to NOT vote, to convince a potential Hillary supporter to not vote, as well.