Was not investigative journalism. Ellsberg provided the content to the NYT. They did show some balls in rejecting the advice of external counsel (and in accepting that of internal counsel) but they were a conduit.

As was the Washington Post, which started publishing soon after the NYT (and managed to fight off the injuction NYT did not). It's possible that the Post only started publishing because the NYT had started, but the value of the NYT itself in the scheme was… limited.