I’ve been using old.reddit since 2008, even after the onset of mobile. The normal UI aka “new reddit” is horrifying and from what I can see the app is the same. There are various features missing in the new web interface as well as various situations where it restricts or lies to you, such as if you’re not signed in and it’s “mature content” or “unreviewed content” and it won’t let you view it - then go to old.reddit and you can view it with no difficulty. But anyway the writing is on the wall that they’re not going to support that interface forever, so might as well give up now.