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

Execution · Grand Arena
Hero shooter with team-up ability synergies.

Optimization · Grand Arena
A real-time strategy classic where perfected build orders and mechanical speed decide most matches.
Marvel Rivals leans Execution (Grand Arena); StarCraft leans Optimization (Grand Arena).
Marvel Rivals leans a little harder on execution, though the gap is small.
Marvel Rivals
Hero aim and ability timing
StarCraft
APM and micro control ceiling is huge
Marvel Rivals leans a little harder on reads, though the gap is small.
Marvel Rivals
Team-fight cooldown trading is prediction
StarCraft
scouting and predicting human opponent builds
Marvel Rivals leans clearly harder on variance.
Marvel Rivals
Map and team comp roll affects
StarCraft
minimal hidden info beyond fog of war
StarCraft leans clearly harder on optimization.
Marvel Rivals
Hero synergies and team-up combos deep
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.