Either you are not using the right products or not the right amounts or not the right application techniques, if your hair is drying out from gel and diffusing I'd suggest your overall routine is not moisturising/ conditioning enough, or not the right balance of moisturising/ conditioning agents with other ingredients like occlusives/ sealants or proteins. Humectants might be good, it does not follow that more is better.
Plenty of Curly Girls conditioner only style, plenty more scrunch out the water with a soft towel instead of plopping, indeed they do in the Deva salon, plenty of us air dry. I talk about gel and diffusing but I mostly do that for social gatherings or interviews, the rest of the time I conditioner only style and air dry - CG is not all or nothing.
CG is somewhat complicated because all your techniques and all your products work together/ affect one another, start out with your hair properties and dew points, choose products based on ingredients and how they will work together, then experiment. Many people are selecting products with so many ingredients that honestly they cannot possibly know for sure if glycerin/ aloe vera/ protein/ shea butter/ the pH of the products is the problem. Sometimes it's good to go back to basics, adding in one ingredient or technique at a time.