Why a treaty-sized Bismarck cannot be judged by gun caliber alone

How threatening would a 35,000-ton Bismarck with eight 330 mm guns be to the Royal Navy?

It would remain an unwelcome battleship opponent; its speed, range, and operational capabilities would determine the full threat.

A 35,000-ton Bismarck with eight 330 mm (13-inch) guns would still be a battleship the Royal Navy would prefer not to fight. Its threat would depend on more than the main battery. Speed, range, and the operations it could undertake would all matter. Britain would deal with the ship if necessary, but the smaller guns would not make it an undemanding opponent.