Why Mediterranean carrier air combat looks less decisive

Was there much less fighter-versus-fighter combat for carriers in the European theater than in the Pacific?

No. Fighters were heavily involved in Mediterranean convoy battles, but those campaigns receive less attention because success meant delivering supply ships rather than sinking an enemy carrier fleet in one set-piece battle.

Mediterranean carrier operations included fighters as well as the better-known bomber attacks. Escorts absorbed damage and shot down aircraft across a convoy's passage. The decisive measure was whether supply ships reached Malta rather than whether an enemy carrier sank in a single encounter. That makes the combat less tidy to recount than a Pacific fleet action even when the fighting was sustained and severe.