Washington also owned slaves.
Quite true, Pop.
However, he consistently called it a great evil throughout his life and worked as he could to limit its spread. Though he wasn’t terribly vocal about his opposition. He spent the last few years of his life putting a plan into effect whereby all his slaves could be freed after his death.
Which he did, unlike Jefferson who through extravagance and incompetence could not do so, assuming he would have liked to, because all his property, including slaves, was heavily mortgaged. TJ freed only a few slaves in his will.
Washington was thus worlds away from the fire-eaters of the 1850s who proclaimed slavery a great positive good.