Mainly not having it be centralised. See, I can host my own. My local scout organisation can host their own. Maybe some other regional body can host their own. They have their own thing going, but they also have seamless integration with other services.

For something I'm self-hosting, there's no way there will be a big user base and a lot of public trails and such crowdsourced. But with a federated alternative I think we could see a very healthy form of crowdsourcing.