My brother died when I was very young, so I never had the chance to discuss stuff like that. About all I got from him was his taste in music (he was 9 years older than me, so I grew up hearing The Doors, Jefferson Airplane, and the like, all the time). However, knowing me, if we wasn't violent (he wasn't, at least at that time), I would have retorted something like "you really need better sources of information". Especially as I get older, I have diminished tolerance for nonsense. Whether in-person, or spam email, or various BS claims on Facebook or Instagram (1poorlady frequently asks me to check things for her, and it is 99% crap). If he were to "blow up", I'd just walk away (I'm not going to get in a shouting match). I can discuss anything with anyone, so long as they keep it civil.

Life's too short to tip-toe around people. I won't ad-hom them in a discussion (e.g. calling him an idiot would be counterproductive). But I'm not going to take on the added stress for no reason. I would resort to avoidance, as I had to do with my father (not as extreme as you describe, but I got tired of dealing with the BS...you can't choose your relatives).

Don't know how old you are, but I hope your relationship with your brother is better than what you've told us. None of our business, of course. If it's common that we become more irritable as we age (as it is with me), it doesn't bode well for the future.