That's just a normal public diplo thread with a fancy name, isn't it? To be able to join the council in-game someone would have to tech Planetary Networks and build Planetary Council wonder ( you'd see that in the log and you did not mention this ).
In PF1 we just use it as a public banter/diplo place with no requirements to enter.
In PF1 we just use it as a public banter/diplo place with no requirements to enter.