Oh, yes. All aspirants to the presidency are insincere. Coveting the job is prima facie evidence of insincerity, don't you know? And anything they do, any action they take on the way to throwing their hat in the ring is done for show and is simply self-serving.
It couldn't possibly be that someone like Cruz surveyed the political landscape, saw no one willing to take the hard stands and fight the good fight, and decided to do something about it.