You'd think this now-tired metaphor for dis-illusionment had passed its expiry date by now. Every ism and its dog has used it as an emblem of that ism's truthiness.

I'm not an adherent to Islam so as you'd expect i would not be in agreement with you. According to this metaphor Islam would be "the mauve pill", a kind of blue pill which is just another illusion. What else would another checkbox list of things-to-believe be other than this ?

Every body of believers has its own institutional structure and thus its own elite, ultimately the elites trace their authority to their religious founders who is either justifiably or unjustifiably idolized/divinized - Man is by nature an idol-making species, he can't help but hero-worship.

The origin of this metaphor was originally from the Total Recall movie, as i recall (!) it didn't feature in the rather charming PKD short story, the film kinda erases the distinction between dream memory and reality, which is closer to the thinking of eastern religions, for which "redpilling" is more apt.