I'll agree with you 100% on the characterization/dialogue of the head honcho being a complete stereotype.
It might be unconscious stereotyping, since Parker wrote the security guys as being smart enough to come armed with weaponry capable of taking down supervillains, but it's still stereotyping, and completely Parker's fault.
As for the stereotyping in the art...
I'd really like to see how Parker describes this guy and the truck security team in the original script. That would let us know how much of the artistic stereotyping is Hotz's own doing.