head to head
Neither is simply harder - they are hard in different places. Die Original Moorhuhn Jagd demands more variance; DOOM (2016) demands more optimization.

Execution · Pure Mechanics
A timed shooting gallery testing aim and speed against flying chickens.

Execution · Pure Mechanics
Push-forward arena FPS where movement and aim are the whole game.
Die Original Moorhuhn Jagd leans Execution (Pure Mechanics); DOOM (2016) leans Execution (Pure Mechanics).
DOOM (2016) leans a little harder on execution, though the gap is small.
Die Original Moorhuhn Jagd
Fast accurate aiming at flying chickens is everything
DOOM (2016)
Aim, movement, glory-kill timing all peak.
DOOM (2016) leans a little harder on reads, though the gap is small.
Die Original Moorhuhn Jagd
Chickens follow scripted flight, not adapting
DOOM (2016)
Demons scripted attack patterns.
Die Original Moorhuhn Jagd leans clearly harder on variance.
Die Original Moorhuhn Jagd
Spawn timing and paths add some unpredictability
DOOM (2016)
Minimal encounter randomness.
DOOM (2016) leans clearly harder on optimization.
Die Original Moorhuhn Jagd
Prioritizing targets for max score matters slightly
DOOM (2016)
Rune and weapon mod picks meaningful.
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.