head to head
StarCraft II: Wings of Liberty asks more than Command & Conquer: Tiberian Sun, and the gap is execution.

Optimization · Grand Arena
Asymmetric sci-fi RTS where tiberium economy management and faction counter-play are the decisive layers.

Execution · Grand Arena
Real-time strategy where hands, reads, and build optimization all matter at the top.
Command & Conquer: Tiberian Sun leans Optimization (Grand Arena); StarCraft II: Wings of Liberty leans Execution (Grand Arena).
StarCraft II: Wings of Liberty leans clearly harder on execution.
Command & Conquer: Tiberian Sun
Stealth unit deployment and artillery positioning need precise timing
StarCraft II: Wings of Liberty
APM, macro, micro-control under pressure
StarCraft II: Wings of Liberty leans clearly harder on reads.
Command & Conquer: Tiberian Sun
NOD vs GDI asymmetry means opponent strategy must be predicted
StarCraft II: Wings of Liberty
1v1 ladder vs adaptive humans modeling you
Command & Conquer: Tiberian Sun leans a little harder on variance, though the gap is small.
Command & Conquer: Tiberian Sun
Tiberium field growth and map elevation create meaningful uncertainty
StarCraft II: Wings of Liberty
map spawns minor; mostly known
StarCraft II: Wings of Liberty leans a little harder on optimization, though the gap is small.
Command & Conquer: Tiberian Sun
Harvester routing and unit counter choices are deeply solvable
StarCraft II: Wings of Liberty
build orders, economy curves heavily 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.