I find the author's description of hardware design, of which I know very little, to match how static typing work. You are explicit about the interface in order to compose while treating individual parts like black boxes.
On static type checking in general my view is: Programming is principally about dealing with invariants. The author is correct to point out that humans are bad at reasoning about more than 7 things at once. Those things we often reason about are invariants and type systems helps us ensure we never violate them. I think even 7 invariants is too many, in C it's common enough to mess up a single invariant (only access this memory while it's alive) that it has caused thousands of CVEs.
Ultimately, why would I not use a tool that helps me get the invariants right more of the time, thus reducing cognitive load?