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 · Pure Mechanics
Push-forward arena FPS where movement and aim are the whole game.

Execution · Pure Mechanics
Motion-control sword-and-gun fights testing swing timing against scripted foes.
DOOM (2016) leans Execution (Pure Mechanics); Red Steel 2 leans Execution (Pure Mechanics).
DOOM (2016) leans a little harder on execution, though the gap is small.
DOOM (2016)
Aim, movement, glory-kill timing all peak.
Red Steel 2
Motion swordplay and gunplay timing carry every fight
DOOM (2016) leans a little harder on reads, though the gap is small.
DOOM (2016)
Demons scripted attack patterns.
Red Steel 2
Enemies telegraph scripted attack patterns
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
DOOM (2016)
Minimal encounter randomness.
Red Steel 2
Deterministic encounters with nothing hidden
DOOM (2016) leans a little harder on optimization, though the gap is small.
DOOM (2016)
Rune and weapon mod picks meaningful.
Red Steel 2
Upgrade choices and learning enemy counters are solvable
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.