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
Alternate-history RTS where economy management and build orders win wars.

Optimization · Pure Optimization
Instanced online RPG where deck-like eight-skill builds decide battles before they begin.
Command & Conquer: Red Alert leans Optimization (Pure Optimization); Guild Wars leans Optimization (Pure Optimization).
Command & Conquer: Red Alert leans a little harder on execution, though the gap is small.
Command & Conquer: Red Alert
Micro and base management under time pressure
Guild Wars
Interrupt timing and kiting in skirmishes
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Command & Conquer: Red Alert
PvP skirmish rewards predicting enemy pushes
Guild Wars
GvG and arena metagame against adapting humans
Command & Conquer: Red Alert leans a little harder on variance, though the gap is small.
Command & Conquer: Red Alert
Fog of war conceals army composition
Guild Wars
Modest drop and spawn randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Command & Conquer: Red Alert
Ore economy and build orders decide games
Guild Wars
Eight-skill build construction is the game's soul
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.