Hmm, I just checked myself, and I was able to read comment threads perfectly fine without being logged in, on both a desktop computer and a smartphone. Obviously old.reddit.com doesn't have these issues, but I'm pretty sure the session on smartphone used the new site, and that let me keep reading without any interruptions too. Either way, if Reddit does this, that's it. Not returning to the site. The internet doesn't…
Unfortunately the way things are going I can see them getting rid of old.reddit.com and i.reddit.com, at which point I think I'll also stop visiting the website (the mobile website is atrocious and I'm not going to install a dedicated app in order to read a forum).
Even if it's infinitely better? I have been using the 'reddit is fun' app for years, and it's the best experience by far. I hate even using my computer to browse reddit to be honest, I would rather sit and be comfortable with a phone. Can't say that about most sites.
On the opposite end, I hate browsing hackernews on my phone so I almost never do. I can't click anything because it's so small. So I just end up using it on the desktop, which is fine I guess.. but it limits my interaction with this site.