When I give tours of the Museum I always highlight the sword and its meaning. George III asked what Washington would do after we had won the war, and after he was told that Washington intended to surrender his commission, go home, and be a farmer, ol' George said "If he does that, he will be the greatest man in the world." Willingly surrendering power was just not done at that time. And of course, Washington did it not once, but twice, when he decided not to run for President for a third term.I don't think the sculptor meant the statue to be disrespectful. I think he misjudged how popular (or not) an element of neoclassical art would be in America. The style was very popular at the time, but while it might be OK for Alexander the Great or the Caesars (not to mention Greek and Roman gods and goddesses) to be shown semi-nude, a semi-nude Washington was not going to fly in the US. In the present day, I don't think John Belushi and the toga party in Animal House is doing the statue any favors. An important part of the statue that we're not looking at because we're all distracted by the semi-nudity and the large foot, is that Washington is holding the sword with the handle out. He is willingly giving up power, something a god or king would not typically do. This is highly respectful to Washington.
But yes, Washington likely would have been appalled at the statue. He was always very conscious of how he presented himself and maintaining his dignity. Democracies at that time did not have the greatest reputation, and most Europeans thought it meant mob rule. So being President of a Democracy, Washington was rather keen to always appear modest, but dignified. Not royalty, but not part of a rabble either.