Me and a group of friends always have a yearly Minecraft stage but it always ends up with only a couple of us actually building and the others only join for the first day and then stop playing. When asked they always say that they just don’t know what or how to build so they just run around exploring and then come off.
That’s a thing. Some people, including myself can’t really build that well not like some of the Master Builders around. So they feel like they can’t contribute. I can never join a server because my buildings would suck compared to others. However you just have to come up with new projects and stuff to build or do. Talk with your friends about ways to get them more involved. Ask them what they want to do and come up with your own ideas of what you’d like to accomplish on the server.