I get your perspective, but just because someone has a red hair, it doesn't render their claims incorrect, or doesn't invalidate anything they say.

I have seen many people being dismissed by others merely because of their voice, which I find funny because they were supposed to focus on the content. It's the content that matters. If the presentation is not to your liking, that doesn't mean that person is wrong. On top of that, you don't need to be factually correct if you are convincing enough; sophistry anyone? Apparently people don't seek for the truth, it's enough if you put a pretty face on stage who has some charisma and you are all falling for it. Be skeptical. Focus on the actual content and ignore the irrelevant things, because they are, well, irrelevant. If you are easily distracted by the speaker's fly being open, that's on you, and yes, the outcome might be detrimental from the perspective of the speaker given the majority of the audience is easily distracted and ignores the actual argument because of the speaker's fly being open, or because he used the word "Micro$oft".

For the same reason we wouldn't need defamation laws if people had better critical thinking skills, as they wouldn't have mindlessly believed the defamation, and the person's life would not have been ruined.

Ultimately, it is your choice. Personally, I am not going to care about the irrelevancies because I focus on what is being said, and not how it is being said. I'm not going to dismiss you because I find your tone offensive, in fact, somehow I manage to not get offended nor care about the tone.

I respect Linus and Theo for their contributions, and I'm not going to judge their quality of code based on their actions unrelated to the code. Surely you, too, care about the quality of code and you won't disregard it when you find out it's been written by a transgender person, right?

If you genuinely care about the argument, you won't disregard it merely because of its irrelevancies, e.g. appearance or behavior you find obnoxious. If you do, then you certainly need to improve your ability to ignore those irrelevant things and focus on the argument.

P.S. I don't deny that presentation matters, but only because there are too many people who are way too keen on dismissing someone's argument because, for example, they find their hair funny. It sounds ridiculous to me, but that's just my opinion I guess.