Desktops and laptops are automatically configured to go onto Desktop Mode, because they're widescreen
When you're on a desktop or laptop, I don't think it's possible to use Mobile mode unless you use a certain software to make the site think you're on a phone
I think the changes to the site are also affecting desktop mode, because on all my devices they changed too
Unless it really isn't meant to be a thing :P
My devices;
1) Windows 11, 1366x768 Lenovo, Firefox and Google Chrome
2) Windows 7, 1920x1080 Microsoft, Firefox