I would say the main idea for me would be to solve problems of regular servers, not to make these bots pretend they are real people.
Time wasted looking for parties is solvable with this.
Timegated playing a big requirement by big clans that ask you to be 10h online if you want to have end game experience is also solvable with this.
I think they should not try to replace real players completely, they should just be an option for smooth gameplay, a tool to remove friction and open posibilities for a solo or small party players, that still want to experience epic bosses, mass pvp and sieges.