I see this asserted a lot, but what's the evidence? I'm going to dislike such a game, for instance: I have zero interest in process-sim D&D.
D&D is a process sim, whether you admit it or not. D&D combat is a very rough combat simulator, but it is one.
Pretending like it isn't, in order to say you don't want new rules to support it simulation-worthy mechanics, when the game explicitly made a difference from the start between modelling magical effects and non-magical ones, does not really matter.
I write weapon collision and damage simulations all day long, and I can tell you, in games you can easily hack together stuff that appears realistic to the end user with little effort compared to modelling physics accurately would require.
This, however, is a mechanic that you could simply not model in a videogame without it being magical or spooky action at a distance. The weapon does not strike the target, so how does it damage me? It cannot. Making statements like "I don't want D&D to become a process sim" ignores the fact that it already is one, however imperfect.
Some of us want, in the course of the game's evolution, for it to make more sense, rather than less.
Damage on a miss is forcing everyone who wants to have a clear understanding of the action and have mechanics directly linked (associated) with game-events to not be able to play or enjoy the game.
Process sim is exclusionary : certain things, we know are not possible, like leaping over tall buildings. We'd have the same trouble with a fighter gaining the ability to jump 50 feet in the air too. To be inclusive of those of us who want our fighters to use plausible, human-achievable things (however extraordinary they may be), the game rules needs to exclude such mechanics that are IMPOSSIBLE to ignore how fake and impossible they are.
I don't need to take this style, but if someone else at the table does, it forces me to throw my hands in the air and makes it impossible for me to enjoy the game. Because every time they miss yet still do damage (without magic or any kind of sensible explanation, which there can't be since it's impossible for a non-god to never miss), my suspension of disbelief is destroyed.
There are plenty of classes with magical powers, this is not one of them. The closest analogy is a melee magic missile. It would be fine to include damage on a miss, on a class like a melee warlock or hexblade. The thing is, you have to call it magical. You don't get to put magic things in the game, give them to non-magical classes like the vanilla fighter, then claim to be inclusive towards D&D players of all stripes.
Your right to enjoy a mechanic is preserved if that mechanic is put in a magical class, but it must have that label if is it otherwise impossible. It effectively means a 1st level fighter cannot miss. I cannot support any set of D&D rules that includes this.
Quite aside from the innumerable other, non-simulationism points against it that I brought up. And there are many.
From the agency of the dice being removed, to the inversion of frequency of use the more accuracy a fighter achieves, thus using it less, to the fact that it makes the weapon moot, including whether it's magical. I mean, you get a magical weapon, if gives bonuses. Guess what, this ability does not benefit from them! A cleric's bless? Nope! It makes you use your fighting style LESS often.
There are dozens and dozens of scenarios aside from the druid flying through the gate, that took me two seconds to come up with. The point of that is that OAs are insta-stop for fleeing enemies who tend to flee when they are about to die. This mechanic is pure, unadulterated garbage from any point of view. It doesn't belong in D&D, period. And certainly not in the fighter class. It would still stick out like a sore thumb even if it did get pushed into the warlock exclusively, because no class should have a single feature that allows them to completely bypass ALL the normal rules of combat : AC, Adv/Dis, Blindness, Prone, benefits from magic weapons, benefits from weapon choice, etc. You use an artifact-level greatsword and it doesn't benefit your use of this ability one iota.
It's completely broken and bypasses all critical combat resolution mechanics and modifiers, except for your foe's current HP. Every other fighting style still uses AC as-is : Protector, Defensive, TWF. They all modify the use, not completely circumvent, of those game stats and mechanics. You know, the ones the designers painstakingly got us all to give them feedback on. Yeah, let's just ignore how D&D combat works entirely, let you skip to the front of the line, and bam, damage at-will with no roll.
Terrible, terrible mechanic.