While delusional thinking is common to religions and especially cults, provided you do the thing religious conservatives hate and actually think through your religious faith, those problems can be avoided. But crafting a sensible, rational, and informed religious faith is a much harder task than a mindlessly religiously conservative one. Thus ease, convenience, and human laziness lead to the latter propagating. But those dynamics are a consequence of human nature: the problems of religions happen because religions are made out of people. Those problems are as inevitable as weeds growing in the garden, and the problem is that the lazy gardener will simply declare the weeds God's chosen flowers and thus don't needed to be weeded out. And not having a religious faith is not necessarily a good solution for those for whom their faith provides central structural components of their mental makeup. It is easy to be simplistic about religion and faith, some declare it absolutely true beyond question (esp. religious conservatives), and others declare it unquestioningly delusional. Both sides associate mainly with those who agree with them, and so anti-religion quasi-cults form, built on the same human dynamics that power religious cults and echo chambers. Humans are complex, complexity is a b****, and we are easily seduced by things purported to take that complexity away.
