Demilich not reporting for duty

[Edi]

100% certain. It has been a development decision to make Dominions 3 to be playable also on lower end computers and slightly older systems. I was surprised to learn it myself, but when given the reasoning, I agree.

I suppose the limit could be increased to 150k or 200k, but the slowdown and performance hit increases linearly with the number of units in the game.