Good point -- The way I described it really applies to _any_ object floating in water.
I don't have much experience with ship design, but on small boat design you can rely mostly on the geometry of the boat to produce a sufficient righting moment even with a very high center of mass.
Some off-shore speedboats have really incredible self-righting because they've been designed to always have positive stability at all angles. One of my favorite videos of this in action: https://www.youtube.com/watch?v=Y2i1fOJ-itw
The trick is to draw a low-mass object with high displacement, which happens to be possible because of the existence of, uh, anti-iceberg? that has negative mass.
Yes, small boats are often constrained by shallow water, so they cannot have too much ballast not to mention things like bulb-keel. This means the hull needs to be sufficiently broad and flat.
Some off-shore speedboats have really incredible self-righting because they've been designed to always have positive stability at all angles. One of my favorite videos of this in action: https://www.youtube.com/watch?v=Y2i1fOJ-itw