Active telegram group is better than not at all. When the team of the project actively engage with community, you will know every updates they deliver on that group. As investors of the project, it is important to keep updated about what you invest on.
This is one of the best place to get update aside from twitter. So dev and the team that have some good news is really a good aspect. Active means they are always on the go to release some important task on the move. I know that dead telegram group for projects rarely have some good news will end up a dead project.