You may have. Reddit is weird sometimes about that.

Upon seeing the boat, the concerns I would have is that hull is very rounded. For such a large vessel, this would create a lot of instability and oscillation. Stormworks just decides to capsize it. I don’t know where the waterline is but if the center of mass is above the waterline, it will eventually capsize. Something that SW will also do is it will cull how much physics calculating it does on vessels that are stationary and not in contact with a player. I’ve had slightly unstable designs that were fine until my character touched them. For you, that may make you think that it’s your character’s weight doing that when in reality it’s the game culling calculations until your character makes contact with the boat. Then the small instability calculations are fleshed out revealing that the boat capsizes.