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

Execution · Practiced Mastery
The 3DS Mario Kart that added gliders, underwater driving, and kart customisation.
Execution · Practiced Mastery
The original kart racer where drift technique fights item luck on Mode 7 tracks.
Mario Kart 7 leans Execution (Practiced Mastery); Super Mario Kart leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Mario Kart 7
Drift boosts, gliding, and underwater control
Super Mario Kart
Hop-drifting Mode 7 corners is genuinely technical
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Mario Kart 7
Online lobbies reward anticipating rivals' items
Super Mario Kart
Two-player battles reward predicting the rival
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Mario Kart 7
Item luck shapes every race
Super Mario Kart
Item rolls swing close races
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Mario Kart 7
Kart customisation and track-specific routes
Super Mario Kart
Racing lines and shortcut mastery
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.