Is this worth reading? Is Foucault in general worth delving into,

Of course it is

If you're not in academia, do not read theory.

I have not read pic related, but Foucault is worth reading. He spent a lot of time researching the obscure, mundane facts of major institutions and you can benefit from his hard work by reading his books. hooray! as for his conclusions, and his "rigor" it is up to you as a reasonable scholar to sort through the trash. madness and civilization is a very entertaining book.

Foucault is worth reading for the critique of normative/orthodox aspects of epistemes/institutions

Only a few people really apply his archaeological/genealogical method(s) but having them in mind is neat

I think he isolated himself by being too much in the French tradition like all of those guys tend to

His later stuff is weirder

I read that recently and it was quite eye-opening, although I found it jargony and poorly written at times.