[AntEater]

Big guns do not always mean big ships, stabiliziation is very important for AA guns.
The 40mm Hazemeyer Bofors mount was the first stabilized AA gun, a dutch invention taken over by the RN and the USN in WW2.

I read somewhere that the old battleships were designed not to negate the movement of the sea, but to translate it in long smooth, rolling motions which were better for the gun and fire control stabilizing systems than shorter more abrupt motions.
So a 35,000 battleship actually rolled MORE than it could have...
But that is most likely not an option for a cruise ship.
Also, it took until after WW2 before active stabiliziation of the ship itself was perfected.
Active systems, either finns or equalizing tanks, were allready put into use before WW2, but were mostly so bad they made things worse.