head to head
Portal asks more than Deus Ex GO, and the gap is execution.

Optimization · Pure Optimization
Turn-based infiltration puzzles with fully solvable deterministic solutions.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.
Deus Ex GO leans Optimization (Pure Optimization); Portal leans Optimization (Pure Optimization).
Portal leans clearly harder on execution.
Deus Ex GO
Turn-based taps, no dexterity at all
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.
Deus Ex GO
Guards move by fixed deterministic rules
Portal
No adversary modeling player.
Deus Ex GO leans a little harder on variance, though the gap is small.
Deus Ex GO
Puzzle states are fully visible from the start
Portal
Deterministic chambers; no randomness.
Portal leans a little harder on optimization, though the gap is small.
Deus Ex GO
Each board is a literally solvable movement puzzle
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.