I can't speak to ATC, but as an Engineer practicing in computer software, I can tell ya that almost anytime Hollywood portrays anything in my field they get it so completely wrong it's ridiculous (e.g., image files that can be zoomed-in on infinitely (and with endless resolution), or quadruple-seekrit double-naught-spy encryptions that can be broken in 2 hrs if the guy just tries hard enough (and rolls up his sleeves)) that I'd be seriously impressed if real ATC guys aren't splitting their sides in laughter during "Pushing Tin".

... that being said, IIRC I did like the movie when I saw it.