I think the whole comparison is a tad unfair. We're getting what, level 4 now?
Wait until level 5 when Wizards and the likes get Fireball and can take out a good chunk of trash in one single action. And it only grows from there.
Spellcasters benefit the most from more levels. Martial classes start good and scale decently, but they can't alpha strike half a bloody screen down the road or have summons and utility to pad out your group.