head to head
Neither is simply harder - they are hard in different places. Portal 2 demands more execution; Tom Clancy's Ghost Recon: Shadow Wars demands more reads.

Optimization · Pure Optimization
A first-person puzzle game where seeing the solution is the whole skill.

Optimization · Pure Optimization
A turn-based tactics game testing unit positioning and ability sequencing.
Portal 2 leans Optimization (Pure Optimization); Tom Clancy's Ghost Recon: Shadow Wars leans Optimization (Pure Optimization).
Portal 2 leans clearly harder on execution.
Portal 2
Portal placement requires some precision but timing is lenient.
Tom Clancy's Ghost Recon: Shadow Wars
Selecting units on a grid demands no twitch
Tom Clancy's Ghost Recon: Shadow Wars leans clearly harder on reads.
Portal 2
No opponent; puzzles are static.
Tom Clancy's Ghost Recon: Shadow Wars
AI follows turn-based tactical scripts, not adaptive prediction
Tom Clancy's Ghost Recon: Shadow Wars leans clearly harder on variance.
Portal 2
Puzzles are deterministic with no randomness.
Tom Clancy's Ghost Recon: Shadow Wars
Hit chances add small randomness to combat
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Portal 2
Solving the puzzle's logic IS the entire game.
Tom Clancy's Ghost Recon: Shadow Wars
Positioning, ability synergy and turn planning is the game
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.