My other INTP IRL friend is a nut though, alex jones type

But is his heart in the right place? (as cringe as that sounds) In other words, does he actually legitimately believe these conspiracy type conclusions to be factually true, and has he considered the evidence behind them (however imperfectly)?

This is different from a more emotional and dogmatic INTJ/INFJ type, who would pick the issues they identify with, and then believe the stories that support that position, without weighing any of the evidence. For instance, someone who shouts "China is responsible for the most carbon emissions" would be less likely to be an INTP, I would bet (because the statement is just so obviously incorrect that you would have to be lying or unquestioningly following the consensus, both of which are not INTP traits).

I definitely subscribe to a few conspiracy theories, and I think INTPs (Ps in general) are more prone to this. Because the P trait is fundamentally about being "open to knowledge". This can lead to some real wacky shit. If you've ever heard of people like Madam Blavatsky, those nuts are definitely _NFPs.