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

Optimization · Pure Optimization
Lane-defense economy optimization against semi-randomised zombie waves.

Optimization · Pure Optimization
Coordinating collectivist town logistics around unpredictable resource islands.
Plants vs. Zombies 2: It's About Time leans Optimization (Pure Optimization); The Tomorrow Children 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.
Plants vs. Zombies 2: It's About Time
Tapping plants quickly only matters in surge moments
The Tomorrow Children
Digging and hauling are deliberate, not twitchy
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Plants vs. Zombies 2: It's About Time
Zombie waves are announced patterns, not minds
The Tomorrow Children
Izverg monsters attack on scripts, not adaptation
Plants vs. Zombies 2: It's About Time leans a little harder on variance, though the gap is small.
Plants vs. Zombies 2: It's About Time
Wave compositions and plant-food drops add per-level randomness
The Tomorrow Children
Island resources appear unpredictably across the Void
Plants vs. Zombies 2: It's About Time leans a little harder on optimization, though the gap is small.
Plants vs. Zombies 2: It's About Time
Lawn economy and plant placement are the solvable core
The Tomorrow Children
Town logistics and labour efficiency are the real system
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.