I think what it comes down to is honesty and trust. The people who show their faces here are willing to back up what they're saying and prove that they are real people, in any other social interaction with people you get to see someones face, its a totally normal thing and has been the way we communicate for thousands of years.
Since the age of the internet people can say and do what they want without any fear of others opinons or judgement, and as a result the things they say can tend to drift from the truth as they build up this persona of who they present themselves to be, and when challenged are able to use this as an impenetrable shield that protects them from the things they say. There are varying ways of gaining trust with someone, but I think the principle method is showing weakness, which on the internet is your face, you submit to the other person and they submit to you and this is where the trust forms.
I can't take anyone seriously here who isn't willing to show their boat, because I know the only reason you won't is because you are afraid. If its afraid of judgement or mockery fair enough but just know this is how people think and if you're going to have strong opinons here they're probably not going to be respected unless you show a little weakness and a little honesty.