Once ATC gives a crew a clearance and the crew accepts it, the crew's responsibility is to comply with the clearance.
Upon receipt of a flight plan, it is ATC's responsibility to determine a clearance that will not conflict with other traffic.
ATC's responsibility is separation.
Aircrews' responsibility is to fly in compliance with clearance.
ATC does not fly the airplane.
Aircrews do not tell ATC how to do their job -- If you see a green traffic light, do you first check to see that the traffic lights for the intersecting street are red before proceeding?