To that end, it’s several “systems” depending on if it’s used for straight-software development in a department, or manufacturing with technological components, or an entire enterprise using Agile concepts (like SAFe). Each one could be slightly different, and each one is some variation on the philosophy.

What it differs from mostly is a phase-gate approach typified by project management, where a plan is made, a budget secured, and a timeline set. All of those things are of course present in Agile, just in different ways and not one-after-the-other.

The big difference is project management has been around forever; Agile just over twenty years. So the former is what everybody knows by default, the latter sounds very “woo woo” to a lot of people. I think that’s really what the comic is trying to say - Agile stuff sounds silly.