It'll work like a charm, its not like the current report system that GM's "review before acting" is not being abused at all, i'm sure an automated chat-ban will be used responsibly.

On a serious note tho, i understand that you have good intentions by making this suggestion but doubt it'll work, at all.

Even if its used responsibly, i dont see what'll stop them from switching from muted bot on server A and log with bot on server B till mute is lifted.
Even if it was account wide they'd just switch accounts, they got no shortage of those.

As long as we don't have even a basic anti-bot muting or even banning bots will be completely futile.