I think a person can come across as genuine and real without divulging everything about themselves...Opening up here doesn't need to include every photo of oneself, all the information one has...Just genuine commenting, a little personality and openness. I don't think that would compromise a person's personal security too much. It's a choice though and many choose not to do so.
Being a little introverted is not unusual; I'm a quote shy person in real life so it's similar. Here though, I feel more comfortable and so open up a little; I hope people see it as genuine.
Thanks for commenting, I appreciate it.