>>56657515Based on evolution data (
https://tcrf.net/Development:Pok%C3%A9mon_Ruby_and_Sapphire/Early_Pokemon_List) and what we know from the legend hierarchy chart, I think Metagross was meant to be an actual legendary with strong ties to this myth.
Steven was supposed to have a 3 stage meteorite pokemon, perhaps this was originally Jirachi and he would've been a 3 stage. Meanwhile metagross was a single stage legendary.
Maybe they got flipped in development? It would explain why metagross's whole theme is a pokemon that gets made from being combined from pre-evolutions, even though the previous evos have differences in their features from each other.