The "typically" in that definition would suggest that "claiming there's a shadowy group of people who at the same time are both unknowledgeable but also conspiring to hide their own knowledge" is unnecessary to claim disingenuity.

You're on the right track, though; it's worth asking if the people criticizing patents and their stranglehold on innovation are not being candid or sincere in doing so. (The answer IMO is "no, they're being very candid and sincere, in stark contrast to most defenders of contemporary patent law", but it's nonetheless the more relevant question).