After all, someone else could share the exact same position while possessing a completely different character.

We aren't just talking character, we're also talking background experience.

I have never been shot. In a discussion of whether being shot hurts, my opinion is less valuable than that of someone who has been shot because I lack the background experience to credibly evaluate it.

I have never given birth. In a discussion of whether giving birth hurts, my opinion is worth less than that of someone who has given birth because I lack the background experience to credibly evaluate it.

Similarly, if I had dodged the draft, my opinion of the wartime actions of those that served is less valuable than if I had served, because I lack the background experience to credibly evaluate their service.

Similarly, if I had dodged the draft, my opinion that "I know more than the generals" is less valuable than that of someone who did serve, because I lack the background experience to credibly evaluate the knowledge and expertise of the generals.

That a statement is based on fallacious reasoning does not make it wrong.