This only cements in my mind that most philosophers are full of it and don't even know much about philosophy.

People who generalize are generally wrong.

How does an article about 4 or 5 philosophers doubting the coherence of one scientific theory lead you to the conclusion that most philosophers don't know anything about philosophy?

Do you know anything about philosophy, and its many sub-fields? There is a basic cleave between the analytic philosophers and the continental philosophers. The analytic philosophers are ones derived from the natural philosophy of England and Germany who developed the scientific method, where as the continental philosophers are the ones who speak word salad and are generally full of shit.

What it comes down to with both Fodor and Naegal is that, being primarily philosophers of mind, they have strong positions about the nature of mind, which they have written about and defended for decades. They are working from their theories about the mind as a starting point, and judging evolutionary theory in light of it. In order to be consistent with their existing positions, they have to undermine some of the current foundations of evolutionary theory. This doesn't imply that they are creationists, as the article keeps skirting, but rather that they want to, at a minimum, reformulate evolutionary theory from a set of assumptions more consistent with their theories of mind. I.e., they want to get to the same place, but by a different road.

Frankly, both are very intelligent people, who have written very interesting articles on the philosophy of mind. Nagel most famous article is What is it like to be a bat?, the thrust of which is that it is not possible to imagine what it is like to be a form of life that experiences the world in a fundamentally different way, and explores the implications of this on the subjective feeling of experience. Fodor is well known for his "language of thought" arguments, which is a highly specific form of functionalism.

Given all that, however, it is a little frustrating when the philosophers barge into a new field, ignore large portions of it, and start pontificating what it all means. But that doesn't mean that all philosophers, or even most, are full of it, or that philosophy has nothing to offer.