Post by WolfBearPost by RobWhat are the long-term impacts?
https://en.wikipedia.org/wiki/Treaty_of_Hadiach
It would not. You probably did not read this article carefully. By that time an idea of being united with the Commonwealth was popular only among the part of the Cossack elite while the majority preferred Moscow.
Hadiach agreement included return of the lands to their previous owners, Polish schliahta, which meant that the new owners would go back to being serfs.
Vygovsky was not a popular military leader (raised to power by being Khmelnitsky's paper man) and his power was mostly based upon the alliance with the Crimean Khanate, which was going against the interests of the Zaporozhye cossacks and could not be too popular among the majority of population. Why do you think the Tatars agreed to this alliance? By the same reason they earlier allied themselves with Khmelnitsky and then switched to the Polish side: possibility to take local population as slaves.
Then, of course, it should be remembered that there was an additional factor, Tsardom of Moscow, and it had something significant to say on the subject: its armies invaded the territory and had a considerable local support. Notwithstanding a number of defeats they managed to take and held a number of the strategically important places including Kiev.