head to head
Civilization V asks more than Civilization VI, and the gap is execution.

Optimization · Pure Optimization
Optimizing city placement, social policies, and victory routing under randomized map unknowns.

Optimization · Pure Optimization
A turn-based 4X where empire optimization beats turn-by-turn tactics.
Civilization V leans Optimization (Pure Optimization); Civilization VI leans Optimization (Pure Optimization).
Civilization V leans clearly harder on execution.
Civilization V
UI actions need no precision; speed is not a factor
Civilization VI
Turn-based, no mechanical input demands.
Civilization VI leans a little harder on reads, though the gap is small.
Civilization V
AI follows scripted personalities, not genuine player modelling
Civilization VI
AI is scripted; multiplayer adds light adaptation.
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Civilization V
Random starts, barbarian spawns, and goody huts create hidden unknowns
Civilization VI
Map gen, barbarians, and city-state quests vary.
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Civilization V
Hex placement, social policies, and victory routing are fully solvable
Civilization VI
Tech, civics, and yield routing dominate strategy.
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.