The first mistake
... was to announce that this was a 'bot and that people could "teach" it things. They might as well have put a "kick me" sign on it.
Hopefully, the next time MS do this, there won't be any announcements, no "Hi, I'm a bot" hoopla. Just an anonymous "person" joins Twitter and starts saying "normal" things - if anyone on Twitter actually says normal things.
So, the first lesson in machine learning would be to not tell the world that you're a machine. If the people who interact with it don't twig that fact then maybe you've got something interesting going on¹. Plus, of course, Twitter could really use all the new 'bots to boost its flagging membership.
I wonder what will happen when it becomes mostly bots? Will there start to be something worthwhile on it (at last).
 but more probably that its followers are even dimmer than the bot is.