I think you're being too harsh. I've personally said much worse things, and it would deeply shame me to have a trivial statement (not action, statement) follow me in the media for the rest of my life. Especially if it were in a private conversation.
He was careless. Most teenagers are. He was probably not even seriously thinking when he said it. He's almost 30 now. Let's judge the man on what he says today.
Fair enough, I was being snarky. But throw yourself back to your younger days. You've said worse, but how much of it did you really mean?
Now back to today, how much of what you say do you mean?
Read and listen to his words on how he feels about privacy in the digital age. Especially with regard to "expectation" of privacy in a sharing site (silly concept, this privacy business there, isn't it?). If he's grown as much as you believe he has, and if how much Zuckerberg means of what he says is any way comparable to you today in terms of how much he means it, I'd still worry.
Does that still sound like someone you want guarding your basket while you put all your eggs in it?
He was careless. Most teenagers are. He was probably not even seriously thinking when he said it. He's almost 30 now. Let's judge the man on what he says today.