Leveling reductionism is that any task in the game has in itself a "Level grind" design.
The player is forced to accomplish numeric goals instead of specific conditions.
The Character level is tied to all game formulas and is the most important determinator.
The problem with level reductionism isn't the idea of "Character level" but its overarching influence of time-gated progresss - denying players below specific levels access to content and forced level parity in groups.