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

Variance · Light / Casual
A short, unsettling visual novel about intrusive thoughts with no skill test.

Optimization · Light / Casual
A guided tour through a developer's unfinished games that doubles as a meditation on creation.
Milk Inside a Bag of Milk Inside a Bag of Milk leans Variance (Light / Casual); The Beginner's Guide leans Optimization (Light / Casual).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Milk Inside a Bag of Milk Inside a Bag of Milk
no physical skill demand at all
The Beginner's Guide
No challenge mechanics at all.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Milk Inside a Bag of Milk Inside a Bag of Milk
no opponent of any kind
The Beginner's Guide
No opponent; a narrator guides you linearly.
Milk Inside a Bag of Milk Inside a Bag of Milk leans a little harder on variance, though the gap is small.
Milk Inside a Bag of Milk Inside a Bag of Milk
branching text has minor unpredictability
The Beginner's Guide
Entirely fixed and authored.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Milk Inside a Bag of Milk Inside a Bag of Milk
barely any systems to solve
The Beginner's Guide
Nothing to optimize; it is a guided essay.
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.