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 · Practiced Mastery
A physics-driven football game testing tackle timing and play-calling.

Execution · Competitive PvP
Shot timing and play-calling against opponents who scheme around your habits.
Backbreaker leans Execution (Practiced Mastery); NBA 2K16 leans Execution (Competitive PvP).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Backbreaker
Tackle timing and ball control via physics demand precision
NBA 2K16
Shot-stick timing and dribble moves gate every possession
NBA 2K16 leans a little harder on reads, though the gap is small.
Backbreaker
Human opponents add play-calling prediction; AI is scripted
NBA 2K16
Online opponents adjust defensive schemes against your tendencies
Backbreaker leans a little harder on variance, though the gap is small.
Backbreaker
Physics-driven tackles add emergent unpredictability
NBA 2K16
Shot RNG and card packs add bounded randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Backbreaker
Playbook selection and field management decide drives
NBA 2K16
Playbooks, rotations and roster building reward deep study
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.