head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Execution · Pure Mechanics
Inertial piloting and shot timing under escalating debris - an execution test from 1981.

Execution · Pure Mechanics
Classic Tetris execution under audiovisual flow, speed still decides everything.
Asteroids Deluxe leans Execution (Pure Mechanics); Tetris Effect leans Execution (Pure Mechanics).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Asteroids Deluxe
Thrust-and-rotate piloting under swarming debris is pure motor skill
Tetris Effect
Piece placement under speed and Zone timing is the whole test
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Asteroids Deluxe
Killer satellites home but follow fixed logic
Tetris Effect
Solo experience with no opponent to model
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Asteroids Deluxe
Asteroid break trajectories add modest unpredictability
Tetris Effect
Randomised bag is bounded and quickly mappable
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Asteroids Deluxe
Shield management and lurking strategies are learnable score tech
Tetris Effect
Stacking theory and Zone usage have known optimal lines
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.