Technically, Xur and Nightfall aren't the only way to get exotics. My first one came from a random legendary drop from trash mobs and decrypted to an exotic weapon.
English
-
Yeah, I know you can get them from that. But the chances for that are kind of slim, at least for me. Not just because getting an exotic from a legendary is rare, but honestly I barely ever get chest engrams. :P BUT yes you're correct.