I have some experience working as a webdev and I don't exactly understand why "non-desktop-browsers" would "not work" when desktop-browsers work. That isn't the case unless you specifically and intentionally make it that way.
No it's 100% intentional. The mobile web app has been similarly hamstrung to drive you to use the app as much as possible for that sweet sweet native app data collection.
There isn't a desktop app that they want to send you to, but there is a mobile app.
You can enable desktop mode in your browser or, as someone pointed out, stick ".i" onto the very end of the URL.
Or just don't go. I mean, there are whole communities on the Thrediverse where you can creatively complain about Reddit. Not like one has to go to Reddit to find upset people doing that.