That's blatantly false because your first move isn't going to be to use acid under many conditions, same goes for ray of frost, etc. Nor will it often be your second or third action. Nor is party of four wizards only using cantrips going to be a superior composition over every other combination - EA or not. So, the answer is no it's not overpowered. You can argue that it is strong, but when you take a look at action economy and actual game play you won't be using those cantrips in first order of priority.
Gosh, what use could there possibly be for an 18 meter range, 2 meter splash spell you can target precisely, which leaves a -2 AC debuff surface which sticks around forever. What use could there possibly be for an spammable extra 10% chance to hit in a game where the to hit is usually between 40 and 70 percent?
"No it's not OP" is not an argument.
You're literally the person who made a comparison of a physical fighter not being able to match a cantrip as an example of cantrips being overpowered -- you are the one who said that, in the current version of the game, a fighter is WEAKER than a cantrip. That's how stupid you are.
Someone who can't do basic math has no place calling anyone else "stupid".
As far as I can tell the damage goes as follows: firebolt hits or misses dealing 1d6 or 0 damage, the area under the target is set on fire. The target receives the "Burning" condition, which deal 1d4 damage immediately, and one more time during the targets next turn, after which the "Burning" condition is gone. If the target moves through a fire surface the burning condition is re-applied. If the target does not move and stands still in a fire the "Burning" condition is not applied.
The enemies don't have to move through that burning area. If you managed to snipe 2 goblins standing next to each other - good on you, that feels good to me.
Two skeletons, and it does not feel good to me, because Larian said this was a game based on 5e, and that is not at all what the spell is intended to be doing.
That assumption is based on the Fire Bolt cantrip, which says it deals 1d6 fire damage (at level 1-4), which I would assume is bumped up to 2d6 at level 5, following general 5e cantrip scaling. The 1d4 is not mentioned anywhere in the cantrip, but rather is tied to the "Burning" condition. Which I assume won't scale with levels, because it does not scale in DOS games.
The Firebolt cantrip was changed from 1d10 with an additional 1d10 at 5th, 11th and 17th levels to 1d6 direct and 1d4 burning. 6 + 4 = 10. 12 + 4 does NOT equal 20. Of course they're going to scale the Burning status.
It's completely absurd to say with a straight face that the 1d4 won't scale because that the cantrip doesn't mention the 1d4 burning status scaling. The whole reason for the 1d4 burning existing at all is why the direct damage was reduced to 1d6.
My point is that 5e cantrips (apart from Eldritch Blast, which is why it is good) are weaker than multiattack.
We aren't talking about levels where multiattack is a thing. We're talking about the balance we can see in front of us. And if there are rule changes causing a problems of balance with cantrips, it stands to reason that there are likely going to be rule changes causing problems of balance with 3rd, 4th, and 5th level spells too.