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.

Optimization · Pure Optimization
An MMO solved through efficiency routing with niche tick-execution skill ceilings.

Optimization · Pure Optimization
An MMORPG dominated by theorycraft, gear math, and rotation execution.
Old School RuneScape leans Optimization (Pure Optimization); World of Warcraft leans Optimization (Pure Optimization).
World of Warcraft leans a little harder on execution, though the gap is small.
Old School RuneScape
Tick-perfect inputs in high-end PvM
World of Warcraft
Rotation APM and mechanics matter in raids
World of Warcraft leans a little harder on reads, though the gap is small.
Old School RuneScape
PvP wilderness has genuine read element
World of Warcraft
PvP arenas have light read element
Old School RuneScape leans a little harder on variance, though the gap is small.
Old School RuneScape
Drop rates and clue RNG drive economy
World of Warcraft
Loot tables and crit RNG present
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Old School RuneScape
Efficiency, routing, and GP/hour fully theorycrafted
World of Warcraft
Gear, talents, and rotation are mathematically solved
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.