>>58012952
Dragonair's original design also looked more like Dragonite (which was created possibly an entire year earlier under Tajiri's direction), and Nishida is on record saying she preferred to make evolutions look surprisingly different.

And if you go look at Dragonite's original sprite from Red and Green, it looks pretty different as well, and the idea that they were always meant to be one evolutionary family doesn't seem so crazy.
https://m.bulbapedia.bulbagarden.net/wiki/Dragonite_(Pok%C3%A9mon)#/media/File%3ASpr_1g_149.png