Possibly. Maybe we're less susceptible to grandiose thoughts and delusions because of the experience from the cold reality of life. In general, people become more reasonable yet cynical, and that may affect our mindset when taking psychedelics. But on the other hand, that probably won't stop us from hallucinating all kinds of crap anyway. I think we just tend to regard it as just that, and not be too inspired by it. They are more like those "fun facts" that wouldn't take people very far. Of course there are exceptions, but this is just how I see it.
That's because I think that a lot of those epiphanies that come from taking a psychedelic are already within us. In a way, it doesn't really teach us anything new, but it will reveal knowledge we don't usually think about or recognize consciously. So basically, the substance helps us analyze ourselves from within, and not an external source.
That's my opinion anyway. Everyone is different and it seems that the reasons why people take psychedelics varies a LOT. We all got to have at least one reason, and chances are it won't match up with a huge percentage of others. That's just the way it is.
I just dislike it when people belittle others, and many times for shallow reasons. It doesn't have to be me, it could be someone else I don't know and it will still bother me. I'm just like that.
As for the weed bit, I use to smoke it everyday, but now it's only once in a while. It's usually in conjunction with other substances though. There was a time it made me paranoid as well, so I quit for a long while. But during that time I had a lot of problems going on, so I'm sure that played a huge part in it. Things are going well now though (finally!), so I can smoke it and not get paranoid anymore.