That is a super dangerous road to go down. Good people can hold horrible ideas and horrible people can be right about some things (Hitler and the nazis were absolutely right that smoking was dangerous).
As a 99.9% libertarian the idea of messing with other peoples sex lives is completely alien to me, but just because others are wrong doesn't make them bad people; I believe it is important to separate the people from their ideas.
I don't think it is possible to separate a person from their ideas. You are the sum of your ideas. If you hold a bad belief, that is a bad piece of your whole personality.
None of us are perfect. We all have bad ideas sometimes. That means nobody can be an entirely good person.
But the converse is possible; we can separate the idea from the person. And when judging the merits of the idea, we certainly should.
Consider that if you separate all the ideas from a person, what is left? An empty shell of a body? Does it still have a person in it?
I don’t know about the smoking thing but Hitler was famously a vegetarian. Many environmentalists argue that if we eliminated meat production the planet would be better off.
As a 99.9% libertarian the idea of messing with other peoples sex lives is completely alien to me, but just because others are wrong doesn't make them bad people; I believe it is important to separate the people from their ideas.