Pretty sure that the enigma-problems didn't become obvious until after it had already spread a little. I believe a lot of people were exhilarated when the enigma came around because it's one of those "blank canvas" morphs, which is why there's a bit of it in a lot of different morphs. Since enigma syndrome isn't something all enigmas get, there wouldn't have been any way to anticipate it. Not to mention that people weren't as educated as they are now about leopard gecko genetics