Of course we don’t want to be silent, but not until whistler blower would be punished for no reasons, exposing a scam required some protection, staying anonymous is very important too, that’s why everyone should use a spare account to make scams accusation.
Why should anyone need to have "spare account" on this forum to report scam? Any user on this forum can be anonymous, we do not need to provide any personal info to sign up, only e-mail address - and we can use Tor / VPN to access this forum.
I know some scammers will try to take revenge on user who discovered them in their dirty intentions, but what can they do if user is clean&respected member of this community? They can open new accounts and fabricate all kinds of nonsense in reputation board, but it's mostly all they can do.
I can agree with OP, there is no justification in turning the head to the other side when we see something bad - by doing that we help scammers to scam others. In case of cryptocurrency it is very easy to scam people, therefore it is always necessary to be at the highest level of caution.