FS is somewhat strange with its warship classes. The PoW and the repulse both weren't destroyers. Battleships and their equally armed but faster bretheren (less armored Battlecruisers) are designed to blow away other ships and such posses less AA defences.
The wiki says they were escorted by four destroyers, all combined they had a rather good AA defence, but without the carrier as much as 86 bombers screwed fiery explosive death right up the brit's asses. Too bad, I like brits 
The majority of Brit destroyers did not have power-worked dual-purpose guns and hence their many batteries were, at best, marginally effective in an AA role. (It's rather telling many of them eventually had to give up their after torpedo tubes for a 4" high-angle gun.) Furthermore at that point in the war they would have been bereft of any sort of light AA gun, and their medium AA gun would have been the the 2-pdr pom-pom (as it was through almost the entire war) which was a very advanced weapon when it was introduced into service...11 years before.
Prince of Wales had a useful battery of 5.25" guns to call on, but they had about half the rate of fire of a US 5" mount, and at that point in the war lacked much in the way of fire control.
Despite 6 years of battle in the North Atlantic against submarines, and numerous engagements in every sea bordering the European continent against surface ships, for the RN in WW2, death usually came from the air.
