Exactly backwards and incredibly ignorant. The country was founded on ideals of liberty and equality, it just failed to live up to those ideals for a long time. That’s why great Americans like Frederick Douglas and MLK Jr. invoked the founding ideals to push our nation forward. https://twitter.com/thejcoop/status/1299133451380183042

Here is what MLK Jr. said about the "magnificent words" that represent those ideals in the founding documents during his "I Have A Dream" Speech:

Frederick Douglass explained that the Constitution and the government "are distinct in character as is a ship and a compass"

Here is his whole speech arguing in detail why the Constitution is an explicitly anti-slavery document: https://www.blackpast.org/global-african-history/1860-frederick-douglass-constitution-united-states-it-pro-slavery-or-anti-slavery/

That Douglass speech included an in-depth evaluation of the three-fifths clause (which several people are citing in my replies) and why that clause was further evidence of the Constitution's anti-slavery position.