Because the power of one individual keeps going up. Just relying only on your own judgement without at least deferring first to a higher authority and attempting to get the issue addressed with their help is reckless and could get a lot of people killed.

Yes people should take a personal stand sometimes, but they shouldn't start there. I understand that previous NSA whistleblowers were gutted, and that was stupid of the NSA because that secret was getting out at some point, but in either case talking to a senator is way, way, way better than talking to a random journalist. There are plenty of reasons not to talk to journalists, not the least of which is that they're often spies. Bringing all the material to Hong Kong was also reckless, though it is possible he took countermeasures to stop himself from giving up the password if he got tortured at the border.