head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is reads, and it is a single point.

Optimization · Grand Arena
Modern AoE balances macro hands with adaptive multiplayer.

Optimization · Grand Arena
A real-time strategy classic where perfected build orders and mechanical speed decide most matches.
Age of Empires IV leans Optimization (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.
Age of Empires IV
APM and micro matter, lower than SC2
StarCraft
APM and micro control ceiling is huge
Age of Empires IV leans a little harder on reads, though the gap is small.
Age of Empires IV
1v1 ladder vs adapting humans
StarCraft
scouting and predicting human opponent builds
Age of Empires IV leans a little harder on variance, though the gap is small.
Age of Empires IV
map gen minor
StarCraft
minimal hidden info beyond fog of war
StarCraft leans a little harder on optimization, though the gap is small.
Age of Empires IV
civ build orders well solved
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.