head to head
iRacing asks more than Assetto Corsa, and the gap is reads.

Execution · Practiced Mastery
Hardcore racing sim where execution is everything.

Execution · Practiced Mastery
Hardcore online racing sim with PvP wheel duels.
Assetto Corsa leans Execution (Practiced Mastery); iRacing leans Execution (Practiced Mastery).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Assetto Corsa
Demanding wheel control, braking, throttle precision
iRacing
Brutally precise wheel inputs required
iRacing leans clearly harder on reads.
Assetto Corsa
Light online wheel-to-wheel reads
iRacing
Serious wheel-to-wheel racing vs humans
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Assetto Corsa
Tire and track temp variance
iRacing
Weather, tire wear, mechanical variance
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Assetto Corsa
Setup tuning, car-track combo mastery
iRacing
Setup, strategy, iRating progression
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.