I thought the BB class was no longer relevant in today's modern, missile and drone oriented naval battle fields?
Yes-ish. In a serious fight against a peer-ish level adversary, the RoI on such a ship looks very dubious. But short of that, a huge warship can have great prestige & intimidation value - assuming that it is competently designed, and built, and outfitted, and operated. Naval history is swarming with only-on-paper designs for big warships. And a fair number of real-steel warships which were cripples, glass cannons, or…
I stand corrected, my memory recalled the old star fleet battles BB class(!)