The bigger deal is how many customers will react worse if you engage with them in any way. If that weren’t the case, pointing to the hours, shaking your head, etc, would be reasonable.

Karens don’t have to follow the rules, they’re special! If you don’t understand that, get your manager and I can tell them…

It isn’t stated that they knew it was closed when they arrived. They might have figured it out after the fact.

They stated it was closed, not that they knew it beforehand. And while I personally wouldn’t behave that way and definitely wouldn’t make such a review, I just tried to put yourself in another person’s shoes. If they know that the store is closed, of course this is pretty ridiculous behaviour, but I originally thought about someone not knowing the store is closed and being confused, and then it just doesn’t hurt to clarify.

I personally also had situations where I was confused because a store closed an hour earlier than it said on the door and online.