something came up my mind, that are anonymous users safe on this forum? Because the trust can no be seen by anonymous users, I also think that any flag raised can not also be seen by anonymous users.
You're using incorrect term here.
Guests and anonymous users, they are different. If you have account that is anonymous, you are a user of this forum. If you don't have an account and only visit the forum to read, you are a guest.
So do you mean guest in this topic?
As you can see here, I only change the username to "Anonymous" on request.
Why are people that do not register on this forum not seeing the positive, neutral and negative trust of registered users on this forum when they are able to see their signature and avatar?
You must register an account, login as a member of this forum to see trust, trust feedback. They don't need to do so to see active flag and I believe flag has its role to help guests know what topics belong to scam projects (or highly scam projects).