Below is the answer to this question from 2020.
To force Hotmail.com/Outlook.com load the lightweight web versions, open your mail via one of these links:
Both are working as of now (January 2023)
Sadly, it doesn't work for all accounts. I have two @msn.coms, and for one of them it throws Something went wrong and we couldn’t complete your request. The other one works though. Here's what it looks like.
Once you're in that version, you can go to Settings/Options and make it permanent.
