AuH20 went off the rails in his old age. I was too young to vote for Richard Nixon in 1960 but I did campaign for him. The Nixon of that era was a good man and a fierce fighter against the evil forces of communism and domestic fifth columnists. By the time of Goldwater's ascendency as the Republican nominee, I supported him wholeheartedly and he was the first vote I cast for POTUS.
Sadly, both of them moved away from their Constitutional Conservatism roots as they aged. The stain on Nixon's legacy isn't Watergate but the EPA as well as wage and price controls. As for Goldwater, suffice it to say by the the late 1980's, he wasn't at all the man I admired from the 1960's.
Did Goldwater really change all that much? I think even back in the 60s, he had a pretty strong libertarian streak.