Probably because it doesn't fit with their version of how a team should be lead by Cap. I mean, war isn't won by staring at the map and yelling plays over a comm - but basically how Cap lead the team in TFA and in Avengers: you trust your guys to do what they do best and direct them to get into the best positions as possible. Not really hard.
He directed Hawkeye to head to higher ground = he knew that Hawkeye's best when he sees all and due to his experience as a SHIELD agent, he can take and give orders accordingly
He directed IM to handle the perimeter = he knew that since Tony has ranged weapons/can fly, it's easier to keep the action in one confined space
Directing Thor to the sky is pretty obvious, he can fly and controls lightning with his hammer = Chrysler Building lightning rod
Directing Hulk = smash
Having BW as his back-up, you have another experienced soldier who can be directed to get the job done.