head to head
Neither is simply harder - they are hard in different places. Rainbow Six Siege demands more reads; Valorant demands more execution.

Reads · Grand Arena
A tactical breach-and-defend shooter driven by mind games over angles and gadgets.

Execution · Grand Arena
A tactical hero shooter decided by aim duels and adapting to human opponents.
Rainbow Six Siege leans Reads (Grand Arena); Valorant leans Execution (Grand Arena).
Valorant leans clearly harder on execution.
Rainbow Six Siege
Crisp aim required but TTK is unforgiving.
Valorant
One-tap aim and crosshair placement decide most duels.
Rainbow Six Siege leans clearly harder on reads.
Rainbow Six Siege
Defenders adapt holds; attackers fake and bait.
Valorant
Humans constantly adapt peeks, fakes, and ability timings.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Rainbow Six Siege
Site rotations only; loadouts deterministic.
Valorant
Light spray RNG and unknown enemy positions.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Rainbow Six Siege
Operator picks, gadget placement, and utility usage.
Valorant
Agent comps, util usage, and economy are studyable theory.
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.