The bot’s posts are

Yes, that was the point of my post - can now follow the blog directly.

Microsoft is not posting their content in a federated way

Well, they’re using Wordpress, and Maho has activated the Wordpress ActivityPub plug-in to enable following it. Currently to comment on them you need to login (I guess with MS account?), so yes, would need it to be on official MS involvement for that change to happen, rather than something Maho has done in his spare time, because that would need an organisational change.