The same questions can be said for MonoBook versus Oasis.
Like I said a concern I had for years from Wikia (Or "FANDOM" now is it?) that it will someday decide to get rid of MonoBook, that I'll log in one day to find my settings on Oasis and when I check My Preferences find only the one option under Layout.
After all MonoBook is dated, hardly anyone really uses it and it's mostly incompatable with Wikia's modern features.
However MonoBook does has it's perks, being that it presents it's content more clearly, runs smoother especially for older browsers (less to load up) and while less ads vary on MonoBook wiki's these ads are less clutter to the artcles. So I am very thankful for Wikia for keeping MonoBook despite it being reduntant, it's how I've always used it before MonoBook and happy to keep using it.
How I feel on the layout relates to discussions, even the old discussions had perks that the "continuous feed with category filter" lacks. Such as efficiency in navigating threads: For example if I wanted to look over a thread from a month a go, I'll have to click on a catagory and keep scrolling down and down, all the while expanding the discusions board site on my screen until I find what I'm looking for. Also only 10 threads displayed before you "Load more".
The way we had it before, all the threads titles were listed and had 25 threads per pages that you could browse from. If you're sure the thread you're looking for was a long time a go you could just skip a few pages while checking the date stamp next to the thread. Also being that they were wiki-based, you could use the search engine to find old articles to look for.
You can no longer do that with the current layout. Yes the threads are listed out, but so are the original posts which take up large chunks of the screen and if you want to find an older thread, you have to load up all the threads from now until then.
Imagine browsing your favourite Twitter account that posts jokes, memes and what not and you wanted a particular post from 2012 and you can't google the particular post or use a search for it. You'll have to stretch out that Twitter account and all it's image and video files just to scroll back in time to find what you're looking for. Thats what the current discussions are like for the WIki's I browse.
All in all I'm not critisizing or simply bashing the new Discussion layout because "I'm old" but can't deny that what makes the "new" efficient lacks what made the "old" just as good, if that makes sense. And I understand FANDOM/Wikia is a business that encourages progression for it's media but still it's nice to allow the users options to progress just like how it keeps the option between MonoBook or Oasis.