I don't wholly fathom this progression chart.
I ticked, in green below, the only glyph that resembles anything like a boat, but that "Bronze Script" doesn't resemble 舟.
Doubtless, boats are "horizontal". Their length > their width. All the other glyphs are vertical, so I can't imagine how they resemble a boat.
Boats ought be sealed lest water enters. But my red arrow indicate openings and gaps where water can enter and sink the boat.
What does the curvy tail, indicated by my purple arrows, signify? The rudder?
I screenshot CUHK
and Wiktionary.