head to head
Portal asks more than Milo and the Magpies, and the gap is optimization.

Optimization · Pure Optimization
A short point-and-click hidden-object game about a cat finding its way home.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.
Milo and the Magpies leans Optimization (Pure Optimization); Portal leans Optimization (Pure Optimization).
Portal leans clearly harder on execution.
Milo and the Magpies
Pure point-and-click, no timing demands
Portal
Portal placement timing modest.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Milo and the Magpies
Solo cat adventure with no adaptive opponent
Portal
No adversary modeling player.
Milo and the Magpies leans a little harder on variance, though the gap is small.
Milo and the Magpies
Hidden objects are fixed, fully mappable
Portal
Deterministic chambers; no randomness.
Portal leans clearly harder on optimization.
Milo and the Magpies
Finding objects and solving small fixed puzzles
Portal
Pure puzzle-solving optimization.
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.