Unfortunately the establishment is right about one thing. Most of the voting public cannot be fairly characterized as adults. They are still wrong, however, that they must be treated as children. That only prolongs the problem. Many will refuse to grow up until they have to. Some lessons can only be learned the hard way and some people only learn the hard way.
I don't think Gingrich would have fared any better. Probably worse after putting his foot in his mouth too many times. Romney was the right man at the right time for the job. His potential employers are simply too childish and voted for the fantasy, the con man.