A slave owner during Washington's time was little different than the top few percent who fight against worker safety, higher pay, benefits, etc. Today's Capitalist would still be slave owners if they could. Fuck George Washington and Thomas Jefferson, and quite a few other of that slave owning lot.
Anyone who has done real study of those times can see the likes of Washington were silver spoon fed wanna be aristocrats at the top of the caste. There were more than a handful of Presidents prior to Washington, why are those men not called fathers of our country? While we are at it the Constitution itself was meant to be a form of slavery to the states, and to further strengthen the upper caste of those times.
To answer your question, yes, we should judge them by the same standards we claim to have today if those standards are good. The anti-slave standards should have been the standard then. Bottom line: Wealthy people always want more, and feel entitled to have it.
Great article. "Ethics and morality are timeliness" Indeed.