I would not be surprised if Bush loathed Trump. Trump has called him out on the Iraq War from the get go. he has humiliated his brother (the ultimate affront to W is to attack his family), and he has pointed out that our country was moving towards a bizarre monarchy where being president seemed to be a right if you came from the Bush or Clinton families.
Also, Bush is very much like McCain - a Republican establishment guy, and Trump is not really a Republican at heart, he is...well....he is Trump. And few people are more Washington Establishment than the Bushes (and Clintons).
Still, Bush did not mention Trump as the cause of any of the things he mentioned. The phenomenon he describes are for the most part true, and have been brewing for the past decade - certainly under Obama. His comments could as easily have been referring to condemn Obama as at Trump, and they may not have been referring to either rather than to what is going on in society in our country in general.
It IS noteworthy that Bush kept quiet through all of the Obama Fiasco to speak up now, so i will give you that. but again, this is no more surprising that McCain's behavior.
These people are ALL part of the swamp.