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 · Grand Arena
Fast tiberium-economy RTS with a once-thriving competitive 1v1 scene.

Optimization · Grand Arena
Blizzard's hero-centric RTS where build-order theory meets surgical unit micro against humans.
Command & Conquer 3: Tiberium Wars leans Optimization (Grand Arena); Warcraft III: Reign of Chaos leans Optimization (Grand Arena).
Warcraft III: Reign of Chaos leans a little harder on execution, though the gap is small.
Command & Conquer 3: Tiberium Wars
Fast micro on squads and harvesters
Warcraft III: Reign of Chaos
Micro of heroes and units decides fights
Warcraft III: Reign of Chaos leans a little harder on reads, though the gap is small.
Command & Conquer 3: Tiberium Wars
Ranked 1v1 rewards reading enemy tech paths
Warcraft III: Reign of Chaos
Scouting and out-guessing a human opponent's tech
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Command & Conquer 3: Tiberium Wars
Fog hides tech switches until scouted
Warcraft III: Reign of Chaos
Creep routes and item drops add randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Command & Conquer 3: Tiberium Wars
Tight build orders and tiberium control
Warcraft III: Reign of Chaos
Build orders, creeping routes, and matchup theory run deep
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.