Here is a rant for any group member who uses Reply All consistently.
My forthcoming guidance to my fellow members of [group name] about Reply or Reply All stems from a few days of not checking my computer for a few days. There were four pages of [group name's] emails that most of us can live without.
If someone wants to thank a fellow group member or add a 1- or 2-word comment, can't they just message the one person? True; those messages are nice. . . for the one recipient.