I agree. She's being extremely patronizing, and worse, making Booster feel that HE'S in the wrong for being concerned about this. Diana's attitude seems to be that grief is on a schedule and Booster's behind.
She shows not the slightest bit of compassion there. Just a rush to closure and complete sanctimoniousness, the kind I'd expect of her. Which is why I have never, ever liked Wonder Woman. When she has been given a personality, it's something like this.
What she does do is point up the difference Booster is discussing between the "icons" and the more "working-class" heroes(so to speak).