From one of the sub Reddits discussing the ban, it seems like the moderators on the GA violated Reddit's terms of service.

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This is just one reason why the QAnon subs got banned.

On the 12th of August a user on 8Chan posted a vague and cryptic message linking a satirical twitter account to a "global network of baby eating demonic pedophiles". But this wasn't just any 8Chan user, radicalized reddit users consider this to be "drop" from "QAnon" a person they believe to a prophet.

This message exploded through the QAnon network on reddit, where the movement is primarily based. This 'message from Q' was by design an incendiary bomb that was to be widely disseminated to the “Q believers”. This directly lead to owner of the twitter account being targeted and receiving hundreds of threatening messages sent by Q followers.

If you think that QAnon has nothing to do with Reddit. Then you would be gravely mistaken. r/Greatawakening is of such importance to the “Q Movement” that they were directly referenced by “QAnon” in the most recent “drop”.

These subs are becoming more radicalized and more emboldened every day. They openly mark their harassment as “Q sent me”. This hysteria is escalating, and it won’t stop until someone is dead. QAnon is Pizzagate, and it is as every bit as hysterical, deranged and dangerous. The QAnon subreddits are extremist training grounds. They not only promote the radicalization of their users, but unapologetically incite them to commit violent acts. This incendiary bomb was heavily promoted on several subreddits.

The reddit QAnon platform on reddit resulted in the twitter user “S8n” receiving 200+ threats from enraged Q “cultists”. This harassment can be easily found on his twitter account.

We at the TMoR have confirmed that u/itss8n the owner of the @s8n twitter account that was targeted, and he personally reported the harassment to the moderators of the main QAnon subreddit r/GreatAwakening, but they refused to remove the offending post claiming there was "no evidence" of the user being harassed. Instead they deleted his posts begging them to remove their multiple stickied threads about him, even though he explicitly stated he was receiving threats. They then officially then encouraged further harassment, and also provided an article containing his personal details.

Let me repeat that: they shared his personal details – when they knew he was getting death threats from their own users.

Remember why, specifically, the Bill of Rights was written...remember its purpose. It was written to limit the power of government over the individual.

There is no believing a liar, even when he speaks the truth.