I guess because LNS just hasn't felt like doing the reveal yet for whatever reason. I hope that will change soon, I feel like LNS is missing out on valuable community input by waiting so late in the game to announce. Notice on other modules like the Mirage where the community has spotted issues that helped the devs to make adjustments, there is a lot of knowledge in this community.
I understood the hold back when it was still going to be a big surprise, but in the end I still would have preferred an F-14 style announcement in hind sight.
The ED acknowledgement definitely caught me off guard, I really thought LNS would have announced before ED made a statement like that, but at least it is something official. I was surprised there was no word of the F-4U in the email though, perhaps it has fallen behind the Viggen due to carrier ops and a theatre coming with it?