I'd like to know how how they could tell the difference.
So they did something to the brain of the mouse and it didn't remember something subsequently.
Do they know what else the mouse didn't remember? No.
Do they understand this effect? No.
Hitting the mouse over the head with a rock might induce the same effect, is there a meaningful way to tell these two procedures apart? No.
Did they find a nice hook to get publicity for their research by talking of selectively removing distinct memories? Yes.
Would we be somewhat fuzzy-brained ourselves if we bought into this? Yes.