The Trumpster is relieved only because he's not an intelligent man. Comey left hints about the FBI's investigation into the Trumpster/Russia connection with references to British spy Christopher Steele's dossier, VP Mike Pence, AG Jeff Sessions, CIA Director Mike Pompeii, Jared Kushner, and more.

There was plenty that Comey could not talk about in an "open setting" because it was part of the ongoing investigation and/or it was classified. This is far from being over, and although the Trumpster wasn't a target of the investigation when Comey told him as much, most of his inner circle was, and it's very likely he is now.