D&D is one of the most combat oriented RPGs; if you are good at combat, you are relevant
Most likely you have the highest damage output, or second if the Barbarian has Great Weapon Master.
Cantrips are quite bad at damage , except for Eldritch Blast with Agonizing Blast.
The Wizard, even if he has Eldritch Blast1, will lack Agonizing Blast. Even after taking 2 levels of Warlock for it, most likely he won't have the necessary Charisma bonus to use it effectively. Even if he has 16 now, he won't be able to increase it properly, without sacrificing his progress in wizarding.
Sure he can decide to spend all his spell slots in the first encounter, vastly outdamaging you, but from then on he is just an extra mouth to feed that day.
1 The only legal way for a Wizard to have Eldritch Blast is through Magic Initiate or Spell Sniper, which means he will be even weaker in his primary class, having spent his ASI on a feat.