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 · Practiced Mastery
Tests class counter knowledge and objective control with lighter economy than classic RTS.

Optimization · Pure Optimization
Instanced online RPG where deck-like eight-skill builds decide battles before they begin.
Command & Conquer 4: Tiberian Twilight leans Optimization (Practiced Mastery); Guild Wars leans Optimization (Pure Optimization).
Command & Conquer 4: Tiberian Twilight leans a little harder on execution, though the gap is small.
Command & Conquer 4: Tiberian Twilight
Unit micro and crawler repositioning under 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 4: Tiberian Twilight
Class picks and feints against humans reward prediction
Guild Wars
GvG and arena metagame against adapting humans
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Command & Conquer 4: Tiberian Twilight
Little hidden beyond fog of war
Guild Wars
Modest drop and spawn randomness
Guild Wars leans a little harder on optimization, though the gap is small.
Command & Conquer 4: Tiberian Twilight
Class counters, population caps and objective control are studyable
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.