There is no good reason as to why someone should even have to import/create admin scripts for banning people ingame, let alone a group. A group ban is an entirely different problem that is much harder to accomplish for the average user and requires you to self-host an off-platform bot (which is made harder by the fact that Roblox might randomly invalidate the bot cookie if your IP is not static.)
As the user above said, this is basic functionality.