It's not a new thing, it's been creeping in for a long time.. but it really annoys me.
Once upon a time light fiction was 'fiction', Eng Lit (well any Lit.) was 'literature', or 'modern classics', and the 'Classics' meant Plato et al. Leaving a few loose categories and authors to come down on on one side or the other according to judgment.
Now, for the most part, all fiction is just fiction; and Dickens and Austen are now the Classics. Online is a little better but browsing round physical stores, which I used to love, now just irritates & confuses me. I find it really difficult to sift & assess what I'm looking at when Penguin Classics are alternating with modern froth, especially if short of time and you don't want to trawl along every fiction title in the shop. Usually (& it may have a tang of literary snobbery, but it's not to say I would never want to browse other genres, just have them approximately together), I just want to pick up titles from a section and know they should be at least loosely in the same field of writing quality - that way you can narrow down what you might be interested in on a particular day, & it's how you can make new finds. In the same way you wouldn't want travel & cookery lumped in together etc. Sigh.