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
Pure call-and-response rhythm timing with a freestyle layer for top ranks.

Execution · Pure Mechanics
Precise jump execution across fixed levels with secrets to memorise.
PaRappa the Rapper 2 leans Execution (Pure Mechanics); Super Mario World leans Execution (Pure Mechanics).
PaRappa the Rapper 2 leans a little harder on execution, though the gap is small.
PaRappa the Rapper 2
Hitting button cues on beat is the entire game
Super Mario World
Perfect inputs trivialise every jump, spin and cape flight
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
PaRappa the Rapper 2
Teachers rap fixed lines, nothing adapts
Super Mario World
Scripted Koopas adapt to nothing
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
PaRappa the Rapper 2
Songs are fully deterministic call-and-response
Super Mario World
Levels are fixed; nothing hidden survives one playthrough
Super Mario World leans a little harder on optimization, though the gap is small.
PaRappa the Rapper 2
Freestyle scoring for Cool rank rewards learned improvisation patterns
Super Mario World
Secret exits and route knowledge add a modest solvable layer
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.