head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Execution · Competitive PvP
Shot timing and play-calling against opponents who scheme around your habits.

Execution · Practiced Mastery
Planning approaches with recon tools, then executing them under lethal fire.
NBA 2K16 leans Execution (Competitive PvP); Tom Clancy's Ghost Recon Advanced Warfighter leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
NBA 2K16
Shot-stick timing and dribble moves gate every possession
Tom Clancy's Ghost Recon Advanced Warfighter
Lethal firefights punish sloppy aim and exposure
NBA 2K16 leans a little harder on reads, though the gap is small.
NBA 2K16
Online opponents adjust defensive schemes against your tendencies
Tom Clancy's Ghost Recon Advanced Warfighter
Multiplayer squads outflank and adapt to your habits
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
NBA 2K16
Shot RNG and card packs add bounded randomness
Tom Clancy's Ghost Recon Advanced Warfighter
Enemy placements are scripted-but-unknown on first attempt
Tom Clancy's Ghost Recon Advanced Warfighter leans a little harder on optimization, though the gap is small.
NBA 2K16
Playbooks, rotations and roster building reward deep study
Tom Clancy's Ghost Recon Advanced Warfighter
Drone recon, squad orders and approach planning decide missions
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.