That's the Progressive Liberal Socialist mindset. They believe that they have 200+ more years of "progress" over the Founders, so they know better. They never seem to actually KNOW anything about the founders of our country, how intellectual and original they were, and that wouldn't matter to their overblown view of themselves as genius-level Libs, anyway, because they believe we all start out the same, and it's only circumstance that puts people where they are--the "luck" of being born rich, or the "luck" of being skilled, able to become rich, or whatever. They believe there is either good luck, or victimhood and resentment.
And in that victim position, they know more than one who's never been a victim, and they CERTAINLY know more than people who owned slaves (as if that moral failing logically means they were stupid).