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 · Practiced Mastery
First-person melee timing against scripted hordes, supported by a craftable weapon economy.

Execution · Practiced Mastery
A side-scrolling shooting test layered over loot-driven loadout optimisation.
Dead Island 2 leans Execution (Practiced Mastery); Shoot Many Robots leans Execution (Practiced Mastery).
Shoot Many Robots leans a little harder on execution, though the gap is small.
Dead Island 2
Melee timing, dodges and zombie crowd control need decent hands
Shoot Many Robots
Run-and-gun aiming and dodging carry every level
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Dead Island 2
Zombies follow scripted aggression patterns, never model you
Shoot Many Robots
Robot hordes follow scripted behaviours, never adapting
Shoot Many Robots leans a little harder on variance, though the gap is small.
Dead Island 2
Loot drops and zombie spawns add mild run-to-run noise
Shoot Many Robots
Random loot drops shape each build's options
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Dead Island 2
Weapon mods, skill cards and elemental matchups reward planning
Shoot Many Robots
Gear and stat loadout tuning gates harder difficulties
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.