I have been using Copilot for over half a year or something, and I haven't found it to be useful in Word, and it is rarely useful in Outlook. I don't use Excel a lot, so I get a lot of value out of the formulae generation stuff when I have to use Excel.
There are several meetings that I need information from, but don't need to attend. Culture has been to take the summary from a meeting and dump it into the chat after, and if it misses anything add it below it. Really nice for action items and things like that.