Vast majority of boats are unplayable

The coastal vs bluewater DM discrepancy is a big part of this, yes. But also the 3.3 matchmaking vacuum hurts anything 2.3 and above. If I wanted to play destroyers, I’d play destroyers. But often times you’re forced to play destroyers because there’s not enough boats to fight and the destroyers have the speed to get into the coastal areas anyway.

aren’t they made out of woods?

The criticism is not that the boats are unrealistically or absurdly weak. The criticism is that they are put in positions, by the design of naval matchmaking and balancing, where it becomes ritual self-harm to play them.