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

Optimization · Light / Casual
A branching visual novel that tests little beyond exploring choice routes.

Variance · Light / Casual
An exploration of narrative branches that deliberately tests nothing.
Everlasting Summer leans Optimization (Light / Casual); The Stanley Parable leans Variance (Light / Casual).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Everlasting Summer
Reading and clicking choices, nothing physical
The Stanley Parable
Walking is the only input
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Everlasting Summer
No opponent - characters follow fixed branching scripts
The Stanley Parable
The narrator is a script, however much he pretends otherwise
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Everlasting Summer
Route outcomes are hidden only until first playthroughs
The Stanley Parable
Endings are hidden information until you wander into them
Everlasting Summer leans a little harder on optimization, though the gap is small.
Everlasting Summer
Mapping choice branches to endings is trivially solvable
The Stanley Parable
Finding all branches is a trivial checklist
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.