It was always a little astonishing that Wat Tyler rode out to meet the king without a matched entourage of men-at-arms. The lesson of this revolt is the same as any other - the ancien regime must be killed to the last for the rebels to be secure. Their mistake was in packing up and going home, where they were hunted down and killed.
That’s what you get for believing a fourteen year old boy swinging a severed head around and making overbroad promises.