Eh the objective wasn’t to beat the British single-handed, it was to drag out an insurgency long enough for foreign aid to come in and for the British to decide it wasn’t worth it. Which Washington did very well.

His greatest skill was his ability to inspire his troops and keep them fighting through several very rough years. Also, voluntarily ceding power after two presidential terms was nothing short of revolutionary at the time and set the precedent for the next 250 years of democracy.