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

Optimization · Pure Optimization
A narrative RPG that tests knowledge of its philosophical systems and dialogue trees more than any combat skill.

Optimization · Pure Optimization
Lane defense classic about managing a sun economy against shambling waves.
Planescape: Torment leans Optimization (Pure Optimization); Plants vs. Zombies 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.
Planescape: Torment
Combat is deemphasised; the game is built to be avoided or trivial
Plants vs. Zombies
Clicking to plant, minimal pressure
Planescape: Torment leans a little harder on reads, though the gap is small.
Planescape: Torment
NPCs are scripted personalities; no adaptive opponent exists
Plants vs. Zombies
Zombie waves follow set compositions
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Planescape: Torment
Some dialogue outcomes and item discoveries are hidden until explored
Plants vs. Zombies
Wave timing and lane pressure vary mildly
Plants vs. Zombies leans a little harder on optimization, though the gap is small.
Planescape: Torment
Stat allocation, dialogue routing and companion management reward system mastery
Plants vs. Zombies
Sun economy and lane setups are near-solvable
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.