There are a lot of scammers among the projects which held bounty. My experience. The problem is that bountiests cheated accounts with cheated follows, frends, you tubers have cheted subscribers. It seems that there are a lot of work, but now the results. The founders wants to see results.
Yes, it becomes a problem for promotion through to bounty. Social networks are becoming ineffective. But how to provide information to potential investors? Only paid advertising?
Nevertheless, social networks should not be discounted. Just not all teams publish a lot of news, so users do not actively communicate in social groups. That's why such advertising does not work well.
It's sad that the teams themselves make work with social networks unproductive.
If teams tighten requirements for working in social networks, then this will require more payment. Now many act from the point of view of minimum costs.