head to head
Mega Man X6 asks more than Red Dead Redemption 2, and the gap is execution.

Execution · Practiced Mastery
Punishing platforming execution over learnable boss orders and part builds.

Execution · Practiced Mastery
A cinematic open-world western leaning on shooting feel and atmosphere.
Mega Man X6 leans Execution (Practiced Mastery); Red Dead Redemption 2 leans Execution (Practiced Mastery).
Mega Man X6 leans clearly harder on execution.
Mega Man X6
Cruel platforming and boss windows demand frame-tight inputs
Red Dead Redemption 2
Gunplay and Dead Eye reward aim and timing.
Red Dead Redemption 2 leans a little harder on reads, though the gap is small.
Mega Man X6
Bosses are fixed pattern sets
Red Dead Redemption 2
Enemies use scripted AI patterns, not adaptation.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Mega Man X6
The Nightmare System shuffles level hazards between runs
Red Dead Redemption 2
Some hunting and weather randomness, lightly hidden.
Mega Man X6 leans clearly harder on optimization.
Mega Man X6
Weapon orders, armor parts and route knowledge are essential
Red Dead Redemption 2
Loadouts and routes solvable but loose.
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.