As quoted from the linked post.
It looks like you’re part of one of our experiments. The logged-in mobile web experience is currently unavailable for a portion of users. To access the site you can log on via desktop, the mobile apps, or wait for the experiment to conclude.
This is separate from the API issue. This will actually BLOCK you from even viewing reddit on your phone without using the official app.
Archive.org link in case the post is removed.
I honestly don’t think theyll remove it, since reddit relies on mods and mods really prefer old reddit than new reddit
But I wouldn’t be surprised if they did something stupid like limiting it to only mods
It’s literally the same wording as that the API isn’t going anywhere, and the same reasoning as why it won’t go away. Reddit is definitely stupid enough to get rid of it