He used his real name. And a distinct name, at that. There are only 8 results on LinkedIn for "Satoshi Nakamoto", and at least one of them is a fake one. If he truly wished to remain anonymous. And despite this, it took journalists 5 years to find him. If he'd made up a name, he could have probably been anonymous for life. But he chose vanity over anonymity. And now he's an outed public figure. He can no longer sue for 'slander' and must instead argue the much more difficult case of 'libel'.