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

Execution · Twitch Chaos
An endless runner testing swipe reflexes against procedurally generated obstacle streams.

Execution · Twitch Chaos
Sustained reaction-swiping against procedurally shuffled obstacle segments.
Subway Surfers leans Execution (Twitch Chaos); Temple Run 2 leans Execution (Twitch Chaos).
Temple Run 2 leans a little harder on execution, though the gap is small.
Subway Surfers
Swipe reaction speed at increasing pace is everything
Temple Run 2
Split-second swipes at rising speed are the whole game
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Subway Surfers
No opponent - just oncoming obstacles
Temple Run 2
No opponent; the track does not adapt
Temple Run 2 leans a little harder on variance, though the gap is small.
Subway Surfers
Procedural track segments keep each run unseen ahead
Temple Run 2
Procedural track segments keep each run unpredictable
Temple Run 2 leans a little harder on optimization, though the gap is small.
Subway Surfers
Powerup upgrades matter little beyond reflex play
Temple Run 2
Powerup upgrades and objectives add a thin meta layer
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.