You're right! The presence or absence of photographs of the team is not a guarantee that the project is promising or fraudulent ... it's just an element of the site design.
The desire of the team to remain anonymous does not mean that the team is a scammer or has conceived something bad ... people just care about their own safety or do not want to make their private life public.
Yeah, it is their own right to remain anonymous, but it causes harm to project advertisements. Because still biggest part of community members pay attention to information about team
It doesnt seems like a real problem. And I think that if it will be harmful for project so devs will show up