Discord is obviously allowed. We all agree on how stupid it would be if it wasnt. The point of threads like this is not to argue that discord should get you banned, it's to prove that just pointing at the ToS and go "well read what's written" is meaningless. Rules need to be interpreted for the goal they are trying to achieve, not followed to the letter. The ToS are not meant to enable malicious brigade reports, they are meant to solve actual problems. No one who report brigaded had an actual problem with the first streamer they hit, it was just to try it out.
Hardcore rule sticking does not prevent loopholes from being exploited, it creates them. Rather than asking what does a rule say, you should be asking what does it mean to achieve. Remember, if the only thing bad about an action is that it's illegal then it shouldnt be illegal at all. An action has to be illegal because it's bad, not the other way around.
And a lot of mods/third party tools dont have a negative impact or provide more upsides than downsides. In the case of ACT it's already covered under harassment if you decide to be a toxic person with ACT.
I reject this notion that if SE would do nothing after mass reports it would harm their reputation and make them look incompetent. It proves the opposite. It shows that they wont just cave in to some stupid demand just because a lot of malicious people yell about it. Instead they commit to their current approach. What makes them look incompetent is at the same time admitting that the UI features in this game are lacking and then banning people for fixing it.
Overall streamers will survive having ACT off screen and a vanilla UI. It's nothing more than a meaningless token gesture afterall. What I think SE should take a hard stance on is hyper toxic forums like the one that instigated this report brigade. They are not doing it to make the game better, they're doing it for "fun". And SE has the means to act on them. They have the records on who participated in the report brigades and they can terminate any account for any reason. They have the means, they just lack the conviction to make sure their own ToS are used with good intentions.