Also, people do not need formal "structure" to communicate concepts. Is strict formal structure over projects better or less strict?
The closest way of knowing is to run scientific experiments. However, this is akin to running experiments to determine whether communism or capitalism is better. It's brutally hard to come up with an experiment or even the resources to run such a thing.
This is the article's point. If there's no science or theory backing agile or OOP up.... why do we, by default, consider it the "best" way and make it so ubiquitous? His answer is religion. OOP and agile are religions.
I think it's defined by its value proposition - that shipping early and often and getting direct feedback from users produces better products than not doing so.
Which itself rests on the assumption that a product's value cannot be objectively asserted and is only the sum of its users' perceptions.
Agile could be a religion if it comes with lots of worry whether we are doing it the right way. It can also be a set of habits if you just do some practical things regularly.
You all do understand that you cannot really be working together if you never talk in some kind of lightly structured way about what is to be done, right?