It is a plain fact that people rarely distinguish between philosophy, religion, and culture. As a former mormon who served a mission in a foreign country, I witnessed this first hand: American missionaries (mostly from Utah) trying to superimpose their culture on foreigners and calling it religion, while foreign members pushed back (appropriately IMO) when they felt that the religion didn't really clash with their culture which was being stripped from them.

Now I am seeing this from an outside perspective; I'm not a programmer or software engineer but I work directly with them in a weird sort of non-supervisory product manager role. In my opinion, this is no different...in fact, "Agile", which as far as I can tell is nothing more than a hand-wavy underspecified form of Extreme Programming, has so much ambiguity in its definition that you can't ask any two advocates and get the same response as to what it is. And as such, whenever there is a problem with the outcomes of the process, the only apt response is the No-True-Scotsman fallacy...which makes development descend into the phenomenal failure of productivity that all holy wars are.

This isn't unique to Agile. Lean and Six Sigma are also mixed bags of philosophy and process, and they have been mixed bags of occasional success and phenomenal failure.