head to head
Neither is simply harder - they are hard in different places. PUBG Mobile demands more variance; StarCraft demands more optimization.

Execution · Grand Arena
Battle royale survival blending aim, rotation planning, and heavy circle-and-loot RNG.

Optimization · Grand Arena
A real-time strategy classic where perfected build orders and mechanical speed decide most matches.
PUBG Mobile leans Execution (Grand Arena); StarCraft leans Optimization (Grand Arena).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
PUBG Mobile
Touchscreen aim and recoil control set the ceiling
StarCraft
APM and micro control ceiling is huge
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
PUBG Mobile
Outguessing rotations and third-party timing of human squads
StarCraft
scouting and predicting human opponent builds
PUBG Mobile leans clearly harder on variance.
PUBG Mobile
Circle placement, loot and drop locations dominate single matches
StarCraft
minimal hidden info beyond fog of war
StarCraft leans clearly harder on optimization.
PUBG Mobile
Zone rotation theory and loadout priorities are well mapped
StarCraft
build orders and economy are near-solvable
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.