Sometimes, I shoot JPEG, because I find the limitations freeing in some ways I am not going to define
Again, this is an actual phenomenon that is fairly well established and measured. I'm not sure he is obligated to justify its existence from scratch as a video blogger, when this has already been done elsewhere.
However, although it is known to stimulate your creativity, it stimulates it in limited ways, analogous to the limits you placed on yourself technically in the first place. In other words, it's a good way to get yourself out of a rut or to find a style for yourself if you have none, etc., but it will never be as freeing as it is to be creatively inspired
AND unconstrained at the same time. Most of the research I've heard about on this has to do with "writer's block" not photography, so in those terms, constraints are great for getting you to stop staring at a blank page and actually start writing something. But once you're writing at a good clip, you would usually do well to remove the constraints slowly, to avoid writing an overly formulaic or predictable book (even if your constraints are very odd, once the reader picks up on them, it becomes easier to predict the rest of your story).
So in photography, once you have found a style for yourself and have creative juices flowing and know what you want your end product to be, then you should begin shooting RAW + jpeg again. Because then you can just normally use the jpegs (faster and easier and most of the time you will have gotten what you wanted in camera), but the RAWs will allow you to get more keepers by salvaging technical errors and push the boudnaries a little further now and then.
I think the pitfall that the blogger is getting at is if/when you have little inspiration, and you are relying on RAW to let you create a look that you didn't envision during the shoot. This will inevitably yield crappy results. And if so, you'd benefit from trying out jpeg only for awhile. But if you use RAWs more correctly as a technical safety net or technical enhancement tool, not as a creative safety net, then you're probably fine as-is.