In absolute terms, you are correct. Within the context of American history, the legacy of Wilson and FDR have produced significant change that has lasted for seven decades or more, and unless it is reversed will endure to the end of the Republic, and will have contributed greatly to it's demise.
No doubt about it. Too much of the New Deal is still around today. Phasing out Social Security and allowing people to be financially responsible for their own retirement is good social policy. As for the demise of the Republic, I disagree with you. I don't see it in the cards. There is no reason why the USA can't be here 100-200-500 or even 1000 years from now.