The human brain isn't designed for logic, it's a very sophisticated pattern recognition device. So the fact that people fall for such stuff is a feature, not a bug. IE a fair amount of study has been done on conspiracy ideation now, and there is little indication that these beliefs are pathological in any way. So yes, a failure to educate people on logic, critical thinking, and spotting false arguments. Compounded by all sorts of powerful influences in media, advertising, and politics that not only encourage ridiculous beliefs ... science is increasingly being used to encourage them more effectively! Even if both situations were to change (I wouldn't hold my breath) the incidence of conspiracy thinking would no doubt drop, but it's hard to imagine it ever going away.