I've noticed the same thing. The change alerts for devices still identify the admin that made the change, but change alerts for MS (at least, for MS120 series which is all we've got) devices do not.
Going back through our change alert e-mail history, changes on MS devices identified the admin up till at least 12/14/21. There's a 14-day gap where we didn't make any switch changes, and then the next change alert was on 12/31/21 which does not identify the admin. All change alerts after this point do not identify the admin responsible for the change.
Edit: Reviewed the Organization -> Change Log entries, these do still identify the admin responsible, so the information is at least available. Would be nice to have it back in the change alert e-mails though.