Reddit has one of the worst frontends I have ever seen. Not even from a "SPAs are evil"-standpoint. It's just awful. That has deconditioned me very effectively.
On mobile, every single page load asks if I want to use the app instead. I really don’t, but I probably should start using one of the third party apps. I would never use their own app.
Twitter is equally awful. I wish I understood the commercial reasons for having such bad UIs, especially when the UI has been better in the past. Is it just bad statistics, or are these terrible UIs actually increasing revenue/profit?