What did I miss?
I haven't time to read every comment, sorry. So someone has probably already said—
"But F-35As are not designed for carrier ops (no arrestor, landing gear too weak)"
"The F-35C is the carrier variant designed for catapault takeoff and arrested recovery"
"The F-35C has performance (range, payload) similar to the -A and waaay better than the crappy -B"
"The F-35B is now our only option for the carriers, having flogged the 'obsolete' Sea Harriers to USMC"
"The carriers don't have and never will have CATOBAR" systems, thanks to government mind-changing repeatedly during procurement"
The RAF has rarely shared planes with the Navy because the specs of the planes are too different. In the Falklands some RAF Harriers were supplied to augment embarked Shar squadrons but that was possible only because Harriers don't need special equipment for carrier ops.
BUT the RAF will not want to cripple itself by adopting the feeble F35-B. Its payload and range are simply too crummy, in addition to all the multitude of failings shared by all F35-variants.
In short, the F-35 procurement has echoes of Brexit. A series of increasingly stupid decisions fuelled by politics, arrogance and ignorance has led us to a place where there are now no good alternatives left.
The only "good" thing about F-35 is that in any war against a competent adversary, we won't lose the carriers because of the lousy plane—we'll lose them because the carrier "battle group" will have so few escort ships, due to defence cuts, that the ships will be sunk in less than 24 hours anyway, probably by a swarm of Russian vampires.
And if these billion-dollar behemoths were not built to be able to take on a serious adversary ... why was the money spent in the first place? To blow up Tommy Taliban's 21-year-old $500 pickup in the desert, using a £800,000 missile as part of a £3.17m strike mission?