I believe it was Confucius who cautioned us not to judge the validity of something by the person who was propounding it.

This admonition is akin to the logical fallacy of the ad hominem argument.

That person is not admirable, therefore, nothing he says can be true.

This constitutes a serious error in judgment and perhaps a serious lazy tendency as well.

Any proposition, opinion or proposal must be judged on its own merits, and nothing else.