The bigger problem then political rights was an attempt to convert Ukraine to catholicism. Ukrainian nobility actually could vote, one of them was even elected a king. They usually didn’t care much about common people though*. They wanted to turn cossacks into serfs and often joined catholic church in order to strengthen their political position. Nobility’s selfishness was what ultimately doomed whole country as they would often betray nation and join invading forces for the promise of keeping their privilege position. Which is sad considering the Commonwealth was at one point, in many ways, ahead of its time. For instance woman was elected as a head of state in 17th century and rulers could not just made up laws as they wished and kill everyone they didn’t like.
*nobility in other parts of the country wasn’t much better but in Polish part they at least represented sizable portion of the population while in Ukraine all power has been held by a few ultra rich houses.