The fact of the matter is, the bigger companies wouldn't have been interested in the members in the first place. They usually have a definite type and if you don't fit the concept they have in mind, you're out.
(G)I-DLE's fortune came from the fact that Cube didn't have a clear vision of what they should do with the group (hence the delayed debut). That's how Soyeon successfully inserted herself in. The company did not know how to make the best of the members' charms and individualities? Well, Soyeon thought she did. And she proved it.