Not only do you get a deck that size, you get the hanger deck that lives under a deck that size.
And as I said before, the Brits are buying F-35B STOVLs, so it wouldn't be a stretch to also purchase some F-35C carrier variants in the future. Or just weld a ski ramp on the nose of the JFK and maybe another off the angled deck and be done with it.
LOL
now THAT would look weird....