I'm not saying I agree, I'm not really sure how useful it is as a term, seems to me any definition would be arbitrary - we'll always want more intelligence, it doesn't really matter if it's reached a level we can call 'general' or not.
(More useful in specialised roles perhaps, like the 'levels' of self-driving capability.)
Then those AIs aren't generally intelligences, as you said they are specialized.
Note that a set of AIs is still an AI, so AI should always be compared to groups of humans and not a single human. Since the AI needs to replace groups of humans and not individuals, very few workplaces has individual humans doing tasks alone without talking to coworkers.