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

Optimization · Pure Optimization
Board-game distillation of Hitman into elegant fully-solvable turn puzzles.

Optimization · Pure Optimization
A puzzle island where learning each panel's hidden language solves everything.
Hitman Go leans Optimization (Pure Optimization); The Witness leans Optimization (Pure Optimization).
Same score on execution - which means the number cannot separate them. The difference is in what each one asks of you.
Hitman Go
Turn-based taps, zero dexterity
The Witness
No reflex demands; line drawing only.
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Hitman Go
Enemy pieces move on fixed deterministic rules
The Witness
No opponent; island is static.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Hitman Go
All information visible on the board
The Witness
Puzzles deterministic with no randomness.
The Witness leans a little harder on optimization, though the gap is small.
Hitman Go
Each diorama is a literally solvable movement puzzle
The Witness
Decoding the rule systems IS the whole 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.