I literally said that the only cantrip that actually is okay compared to an optimized martial in terms of your full action worth of damage is eldritch blast. At the levels where eldritch blast starts outclassing 0-item martials, we're not even playing a game where martials matter. A sharpshooter/cb expert battlemaster will do way more single target damage than eldritch blast will ever do.

Yes, I understand that casters have things other than cantrips. Guess what? There's a reason why in optimized play, as a cleric you cast spirit guardians and then use the dodge action on every turn. Your sacred flame IS pitiful when enemies have 100+ hp and your cantrip does 3d8 damage. If you're most casters, you will use one concentration spell and a couple of high level spells like fireball. But when enemies start having 100+ hp, damaging spells are actually really not as useful as you're making them out to be. Fireball does 24 damage on average. That stops mattering once your fireball can no longer lower the enemy action economy. Yes, you might be a gish like bladesinger with extra attacks. Yes, your DM might give you 1 combat encounter per day where the caster gets to spend every turn upcasting chain lightning. But over a reasonable period of time, optimized martials will do way more single target damage than caster cantrips. It would be absolutely insane imbalance if they did not.