Sadly, I don’t have a perfect answer to this question. If I could adequately answer that, I would have gone to a bank. AFAIK this is how ICOs work. Community put trust on an idea to make it possible. The first ICO ever was like that only, a person had something in mind, other people thought, ‘ok, let’s see how you take it further’. Your investment depends on your trust level, if you can’t develop a feeling of trust on the proposal, it’s better to let it go. If you feel like, ‘ok, this looks promising enough, I can spare some satoshis for the proposal’, then go ahead.