Well, it improves the odds for your attack/save cantrips. Mage Hand, Prestidigitation, Mending, etc. don't care about stats. But I know you meant for combat, and I agree that it does. But an ASI only improves their hit odds by 5%. Even if you're concerned about cantrip hit odds, I think a case could still be made for picking up more cantrips through Magic Initiate so you have access to more damage types or can target different stats, which will often help you more than 5%.Strong point. Also, even if your spell does take a save, you may be able to target it against a victim who has a low bonus (or even penalty) to that save.
Your caster stat also improves you cantrips, though - or do you not find yourself stooping to cast cantrips often?
As a player, I actually rely heavily on damaging cantrips because spell slots are such a limited resource. But I don't play the wizard who's there to win every small fight. So unless I think the team can't handle it, I'm just going to hang back and toss in some cantrips so I'm not being useless. If it's really important, I'm probably concentrating on a spell. Another important note is that you burn through spell slots a lot slower if you're using some of those great spells like Polymorph or Animate Objects. You can eat through a lot of spell slots with Fireballs and Vitriolic Spheres, but a single Polymorph can usually get you through an encounter (the Dodge action helps if you can't find good cover).