The reason I brought it up wasn't whether the 2023 date is accurate or not, I think we all believe this is the date they are shooting for (whether they make it or not).
However, is this an "announcement" or a "leak"? Some might think there's little difference here but it's important, it's whether Universal actually acknowledges this to be true or not. As of now it's a no (refuse to comment). So to me this was a slip up, something they may not have fully planned for, and we may not get an official announcement until later.
And yes, a CEO can leak. They are too busy to know some of the finer intricacies. I have seen them mess up on ride and restaurant names all the time (see Tom Williams talking about Hagrids Forbidden Forest Adventure). I've seen basic typos from them. They are not perfect people.