George Washington, wise though he was, was pretty much on his own in this. The other Founders didn’t follow through.
As soon as he relinquished the Presidency, partisan politics took hold (yes, even among other Founding Fathers), and it hasn’t let up since. The Election of 1800 is still one of the most bitter contests in our history, though the 2020 elections sure are giving it a run for its money.
Only Washington’s godlike stature and universal acclaim as the general who virtually singlehandedly delivered the colonies their freedom allowed him to carry the respect of the entire country regardless of party.
I would love for us to be able to put aside partisanship and speak with our fellow citizens as Americans first, Republicans and Democrats second, but I’m afraid we need a leader of tremendous talent to unite us in that way, and the conditions that created Washington’s uniquely non-partisan presidency no longer exist.
Heck, even Abraham Lincoln was despised in his time by a huge portion of the country (not least the ex-Confederates) to the point that an assassin’s bullet ended his life. Despite the fact Lincoln is now considered one of the greatest if not the greatest President ever.
Human beings are flawed, short-sighted, temperamental, tribalistic, and bad about making accurate historical judgments in real-time.