You are right about the bad actors seeking to gain power through Agile at any cost —for others, I even have one article dedicated to them. Yet, I would not say that Agile is “pseudoscientific”, furthermore, Agile is applying the scientific method to software development.

As you say, the problem is those "gurus" that want to be the new masters, and they have no clue about what are they doing. If you look carefully, none follows the Agile manifesto principles, they always need to reinterpret them so it makes nonsense. And things as simple as estimates in Scrum, were found in research useless —in fact, just the opposite, damaging— more than ten years ago by the Scrum creators themselves. But, all those "gurus" cannot listen. And for me, the most laughable is SAFe: took for them 12 years to realize that Product Increment is not a period of time, it is an increment of product (they renamed PI from Product Increment to Planning Interval when they realized).

And btw, there was little science, until the Accelerate book research. You should read it.