It is interesting because people perceive titles as being inflated at start-ups compared to the "equivalent role" (using your example) at an established company, and that's partially true, but it's also not.

I'd say the extent of actual impact to business relative to the entirety of the business operations probably remains roughly the same between two people with the same title at a large company and a small company. However, the potential loss (or perhaps gain) suffered from poor (or great) decision-making is likely much smaller on an absolute scale at a start-up, although roughly the same on a relative scale.