head to head
Neither is simply harder - they are hard in different places. Portal demands more execution; Wasteland 2 demands more variance.

Optimization · Pure Optimization
The portal-gun puzzle game whose solutions are everything.

Optimization · Pure Optimization
A post-apocalyptic tactics game where skill tag distribution and action economy control encounter outcomes.
Portal leans Optimization (Pure Optimization); Wasteland 2 leans Optimization (Pure Optimization).
Portal leans clearly harder on execution.
Portal
Portal placement timing modest.
Wasteland 2
Turn-based tactical combat has no twitch component
Wasteland 2 leans a little harder on reads, though the gap is small.
Portal
No adversary modeling player.
Wasteland 2
All enemy factions use scripted behaviour with no player adaptation
Wasteland 2 leans clearly harder on variance.
Portal
Deterministic chambers; no randomness.
Wasteland 2
Hidden skill check requirements and enemy placement create information gaps
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Portal
Pure puzzle-solving optimization.
Wasteland 2
Skill tag allocation and AP economy optimization define effective squads
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.