I’ve recently been testing Mattermost for a family communication platform. I also tried matrix/element and Rocket.Chat. I’m leaning towards Mattermost since the mobile apps (essential for my family) feels the most intuitive.
Element required knowing what features existed and then finding them which isn’t going to work for grandma.
Rocket.chat was good too just leaned towards Mattermost for some reason.
I really wish matrix had a well polished iOS app. The best I found was FluffyChat but even then it felt…not right.