On the other hand, given where WFB Jr. was in the last years of his life, I wouldn't necessarily assume he'd be that enthusiastic about Ted Cruz either.
So I'm not sure that the current crew betrayed Buckley's legacy. Where they are now has something to do with the malaise that he was in in his last years. Buckley was pretty disillusioned in his last years. For one thing, he wasn't as confident about the Iraq War as his associates at the magazine were.
He also didn't have the fight in him that he once did. It seemed like the good fight and the hard work of getting a movement started were in the past. It was clear that he couldn't go on forever, but just what to do and where conservatism should go in the future were unclear.
Buckley would probably have rejected Trump, as he did in his 2000 article, but for outsiders -- people who aren't movement conservatives or Buckley's ideological associates -- Trump 2016 looks a lot like Buckley for mayor 1965, an eccentric millionaire with controversial ideas making a big splash in the political pond.
You could see a tension in Buckley between the thinker who valued intellectual depth and consistency, and the provocateur who wanted to shake things up and bring about change, and that conflict is still alive today, even after WFB Jr. has passed from the scene.
Now, I happen to be a big fan of WFB, Jr. and his sibbling Fergus [Reid] Buckley. But for the Buckley sibblings to conclude that others are demagogues and narcissists is rich fare for some of us.