All casinos use the Curacao license because it is the easiest to get. Yes, the license does not guarantee that the casino will work honestly, so you need to study other factors, such as user reviews, reputation, how long the casino has been operating on the market. If the casino is fraudulent, it will not work on the market for 10 years.
I think people are more inclined to look at reputation, reviews and how long the site has been active than to look at their licenses, I also don't really focus on licenses as the main criterion that it's a good casino, because all casinos can be scams when they really go bankrupt unable to pay and just disappear, many casinos just disappear, so I think finding a casino that is really active on this forum is my main factor to judge and see if this casino is good or not.
I agree to your stated fact that many gamblers do not look at licence, I personally do not always consider the licence of a casino as something or medium through which I can trust if a casino is legitimate or not, reviews from other users is what I've always considered to be the most important factor, then secondly is how long such a casino have been operating.
This two are enough for me, operating license don't really do much, as I have seen casinos close up and disappear with customers money, and the license company, when contacted didn't even respond, let alone doing anything to help customers recover their funds back.