I had enormous success doing Dark Souls 2. nearly broke 10k views on every single episode and over 20k on quite a few of them. But that's because I knew the game inside and out before I did my walkthrough of it. I was informative and showcased many of the mechanics the player would need to learn to use to beat the game. Honestly if I really wanted the views I'd go back and do the same for DS1, but I want to play games I haven't played.
My point is that if you have a game that you know a ton about, and know how to explain it, do a "walkthrough" for it. I'm currently doing Inquisition and I'm finding it harder to be as informative as I was with DS2, mostly because I haven't played through the game entirely. I'm still going to do my walkthroughs, but I love doing those kinds of videos, I don't do them for the growth or anything. If you don't enjoy it, then don't do it. If you expect instant success from it, chances are you don't need to do it. Do it for the love of doing it and that way you wont be disappointed.