When I was playing through Venus and got to the mission where we need to find the Awoken to get to the Garden, my Character (who is Awoken as well) didn't think for a second she might be seeing more of her kind (if there weren't that many on the Tower).
Heck, it might even be the same for the other races.
What I was thinking, was that maybe they could have fleshed out the character (even if it is just some pawn) more or just gave the characters dialogue unique to their races.
Example (From the first Venus mission):
Ghost: "Bla bla bla find Awoken bla bla Rift bla bla"
Awoken: "You mean more people like me?"
Ghost: "Bla bla bla find Awoken bla bla Rift bla bla"
Human: "The Blue guys? I've always wondered where they come from."
Ghost: "Bla bla bla find Awoken bla bla Rift bla bla"
Exo: "More of them? Beep boop, count me in!"
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I mean, you were risen from the dead with no knowledge of the world around you to start the game. I think it's safe to assume you forgot who your people were, or the people you did know when you were alive are long dead