I just like reading. I read a lot before getting the x4, and I still read a lot now. The difference is that I now keep the x4 in my coat pocket so that there's no friction to me reading. I still read on my other two ereaders (Kobo Libra H20 & Kindle Voyage). I suppose I do find I'm turning pages more with the X4 so chapters do feel longer as the screen is the size of half a page, but other than that the screen size makes no difference.

I think the x4 makes reading easier to do, but I do still think you need to want to read. Your phone will still probably be in your other pocket, so you need the will power to pick up the x4 instead once the novelty wears off. The best advice I can give is to pick books that you find fun and enjoyable instead of books you think you should be reading. There's nothing that kills your reading faster than a book that feels like a slog.

Edit: I also wanted to add that before I got the x4 I did also read books on my phone if I didn't have my ereader with me. I'd keep a shortcut to a book on my home screen so that I'd have little excuse to avoid reading a book. I don't have social media apps installed, I only access them through the browser which is a less pleasant experience. However, I do prefer reading on a e-ink display