Diablo 4 having character customization (face, skin, etc.) kind of undermines this in my opinion, though i guess it sort of still works. I assume Diablo 4 will make the protagonists more like generic no-name heroes.
Also, Natalya is not the Assassin you play as in D2, right? Pretty sure not.
You gave them all names though, right? Fair enough I guess. SKyrim makes you a specific character, despite being totally random and generated by the player. I guess Mass Effect does the same thing with Commander Shephard.
They should be your own alts, but they advance, when active as a follower, at 10% normal rate and cannot benefit from extra XP awards/shrines/pylons/events.
That’s called baiting the waters, i.e. they create a contentious or incendiary topic, contribute just enough to get people worked up, and then sit back and watch the chaos they caused as everyone else fights each other. They only come back if the thread is popular but looks like it’s slowing down, then they throw a little bit more chum in.