I don’t think community servers would fix any of the problems. In fact, I think it’d create more.
Currently, the player base of DB is pretty small. Even at peak hours there are a ton of empty official servers in both US regions. Then of the servers that have players on them, there’s a significant number of low population servers.
Allowing community hosted servers would just spread the community thinner.
Clans and teams, so long as they don’t live too far from each other, can already create private servers right now.