It's not used just strictly towards women though. You can argue it's used almost as much towards men in One Piece as well. Hell, in Wano alone, pretty much all 9 of the scabbards fell victim to it. Oda just likes the "Damsel in distress" trope. Woman, man.... Makes no difference.
At the end of the day, it's used to set up the Straw Hats always being the ones to save everyone.
At the end of the day, it's used to set up the Straw Hats always being the ones to save everyone.
Also, you did hit the nail on the head with that last bit…they’re the protagonists, so at least the women on the crew have better backstories and motivation, but that’s two characters in a) a ten-person crew, and b) a series with a hundred new faces with every arc change, not the best ratio by this measure.