A license won't stop gambling from robbing you, but it will help identify who owns and help local authorities look for thieves if an investigation is opened.
I believe, however, that today this doesn't help much, as Curaçao companies (for example) intermediate several processes for acquiring licenses from other companies located in many countries, everything is just a bureaucratic process in which the sole purpose is to collect fees for the government and these intermediation companies.
This still helps a little, as not every scammer will want to open a gambling site, spend it to license it, and then run a scam.