head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is variance, and it is a single point.

Execution · Practiced Mastery
Executing memorised high-speed routes through deterministic platforming levels.

Execution · Practiced Mastery
Momentum-driven execution over fixed levels rewarding memorised routes.
Sonic Generations leans Execution (Practiced Mastery); Sonic the Hedgehog 3 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.
Sonic Generations
Holding speed through precise jumps and boosts is the test
Sonic the Hedgehog 3
Holding speed through fixed hazards demands sharp reactions
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Sonic Generations
No opponent; bosses are fixed patterns
Sonic the Hedgehog 3
Badniks and bosses repeat identical scripts
Sonic the Hedgehog 3 leans a little harder on variance, though the gap is small.
Sonic Generations
Levels are fully deterministic
Sonic the Hedgehog 3
Levels never change between runs
Sonic Generations leans a little harder on optimization, though the gap is small.
Sonic Generations
S-ranks come from memorising optimal routes and shortcuts
Sonic the Hedgehog 3
Route choice and emerald collection reward memorised play
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.