The number "1,000 km" should be replaced with "3,000 km"...
F35 is advance jet no doubt, but so is J20. But the LHA, as well as any other ship, operate within 1,000 km from Chinese shore is at risk of being hit by missiles.
I think you and I have the same idea.
In a conflict between peer rivals, shore based anti-ship missiles are going to make it VERY difficult for an enemy ship (or a fleet of ships) to attack a defended shoreline. Of course any goal can be achieved if enough money is thrown into it but in this case the costs would most likely be prohibitive.