This all sounds specifically targeted. If you're not in the US and is not a Smash fan, most of the value dies. For the broader Nintendo fanbase, a proper press conference would be better.And for the mainstream press coverage.
Why? The broader fanbase will still be watching a stream either way.
A press conference is for the press; directly benefits only them. With the Digital Event the press will be getting all the same information they usually would, so they can report on it in exactly the same way if they so choose. And they should.