If one where to think that Trump where the lesser of two evils would you discourage them from voting Libertarian?

For most people a vote for Trump or Biden is actually a wasted vote. Most states are solidly Blue or Red so voting R/D won't change anything. It is far more likely that your single vote for a new Party's candidate will get them over the threshold to maintain ballot access for the following election cycle, than your vote for an old Party's candidate will get them over the threshold to receive the plurality of the vote. Maintaining ballot access for new parties allows them to spend more money the next time actually getting out their message and building votes rather than having to spend most of it paying petitioners to get back on the ballot again. Eventually this could lead to a more representative multi-party system in the USA. But treating every election as "the most important election of our lifetime" and refusing to vote for a candidate that more closely represents your values rather than the one more likely to beat the candidate you dislike most, purpurates the system of abuse. Its like a person returning to their previous partner that verbally abuses them because they fear their partner that physically abuses them.