Trump provides a unique opportunity to disrupt the establishment. Of course, we are gambling, but with the establishment we aren’t gambling....we know we don’t like what we are getting.
Cruz had to eventually more over closer to the establishment, since he doesn’t have the money to run a national general election campaign.
Trump does, so I don’t think Cruz is much of an anti-establishment candidate. He might come through, but probably not.
I agree it was always necessary that Cruz move towards the establishment if he made it far into the race, but it was not necessary that he cozy up to them instead of working with Trump and against them when push came to shove. In doing that, he has shown where his loyalty and tendencies lie. He, like Rubio, is conservative in many boilerplate theoretical ways, but by being part of the establishment, makes himeself part of an organization that is antithetical to conservatism.