Emperor's Gift / Mission rewards

Anyone knows how this works? Is it just RNG? I’m level 12 and I’ve gotten a few. But I feel like they are lacking and it seems like some people are getting them often, while others almost haven’t seen a single Emperor’s Gift during their playtime.
If it really is RNG, isn’t that a tad unfair? Or am I missing something?

Being 30, I’ve been gifted a blue curio, 2 purple swords (not even good ones), rest were junk greys and then only very rarely. Maybe 8 items in the 52 missions I’ve done