I've never heard a concise reason yet why the British Government went for through-deck carriers and the F-35B from the start. There has always been a suggestion that the R.A.F. were worried that angle deck carriers would be capable of carrying a wider range of types and therefore actively tried to influence favour toward the limiting B and through-deck, lest the attraction of plonking all fixed wing high performance aircraft on the carrier fleet took hold. I find this taking service rivalry too far, but it's a theory advanced by some!?
FB