What should a good cookie dough look like?
Cookie recipes vary. There is no single consistency that all doughs should have. The proof is in the finished cookie. 

Some of my favorite recipes produce doughs that are sticky enough that I can't "drop" the cookies onto the sheet without using my finger to scrape the dough out of the spoon. In these cases, it's easier to use an ice cream scoop with a triggered blade that will clear the dough from the scoop. Another trick is to refrigerate the dough for four hours, overnight, or for as many as three days. This will give the flour a chance to absorb more of the liquid ingredients. In addition, chilled dough is easier to work with, and produces a superior texture in the finished cookie. I add this step to nearly every cookie recipe. 

I want to address, though, your concern that the dough you make doesn't match what you're seeing in pictures or videos. This could be due to the way you measure flour. There are several ways to measure flour, and each of them can produce a different actual amount for the same called-for measurement. Not only that, they may produce different actual amounts each time you measure. I assume that most modern recipes are tesed with a "scoop and level" method, unless something else is indicated. However, measuring by weight is more accurate. I convert all my cookie recipes to weight measurments. That way, I can ammend or reproduce them with complete accuracy. Lastly, I want to address the integrity of the relationship between written recipes and the pictures or videos that accompany them. Over many years of experience, I have found that relationship to be rather loose.