From The New York Times:

“This is a problem for Biden because in cyber, there’s a temptation to be stealthy and send your message in a very quiet, targeted way, but now, having made the threat, he has to say to the American public and the world, ‘This is what we did,’” said Paul Rosenzweig, a scholar at the free market advocacy group R Street Institute and a member of the American Bar Association’s Cybersecurity Legal Task Force.

“And some of the most important effects are very hard to do in public,” he added, because they can risk revealing American capabilities.