This post on Microsoft's Outlook Blog has a new update added to it, explaining that Microsoft will not be proceeding with AMP support in Outlook.com/Hotmail:
Update (September 9th, 2020): Today we are announcing that, based on the results and feedback we received, the developer preview of AMP for Email will end on October 1st.
After that date, AMP for Email will be turned off in Outlook.com. Emails that used AMP will instead render using regular HTML; there is nothing extra email senders need to do for this fallback to work automatically. If email senders want to send dynamic emails to Outlook users, we encourage you to leverage Actionable Messages instead.
[H/T: All Things Email. It's a great newsletter-- you should subscribe!]