I'm very confused regarding the concept that Specialists should be as good as omnicrafters... Do people just not know what what it means to be a Specialist?

"A Specialist should not be better" does nothing but display a gross lack of understanding for what the word even means... News flash though, if you want to Specialize in everything, nothing is stopping you. This isn't real life, where you can go to medical school become a general practitioner, or specialize in cancer treatment, or bowel disorders, or pediatrics, or whatever. This is a video game. You can make one character who specializes in Weaving, Leatherworking, and Goldsmithing, and you can make another which specializes in Armory, Blacksmithing and Carpentry.