head to head
Neither is harder. They score identically on all four axes, so the difference between them is in kind, not degree.

Optimization · Pure Optimization
Tower-defense math wrapped in a city-building economy to optimise.

Optimization · Pure Optimization
Optimizing game development decisions around hidden genre-topic match formulas to maximize review scores and revenue.
Bloons Monkey City leans Optimization (Pure Optimization); Game Dev Tycoon 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.
Bloons Monkey City
Tower placement is unhurried clicking
Game Dev Tycoon
All choices are menu clicks with no physical ceiling
Same score on reads - which means the number cannot separate them. The difference is in what each one asks of you.
Bloons Monkey City
Bloon waves never adapt to your defenses
Game Dev Tycoon
No adaptive human competitor to model
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Bloons Monkey City
Captured tile layouts and special events vary mildly
Game Dev Tycoon
Review scores and trend timing have meaningful randomness
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Bloons Monkey City
Tower math, city economy and unlock routing are the whole game
Game Dev Tycoon
Genre-topic-audience matching and R&D investment are learnable formulas
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.