Your reading history backwards. You assume that while 1970 protest, leads to 1980 protest and that lead to the fall of the Soviet Union. However that is wrong way to look at it, the right way is that in 1970 the Soviet Union had the will do stop the protesters, but not later. Those things mostly have to do with the discussions and political institutions the elites were working in.
The protesters in late 1980 might have been larger and more popular, but if the Soviet unreleased it might, it would not have mattered.
Nope. Totally wrong. Those early protests, even though seemingly unsuccessful at the time, gave the people one important thing: hope.
Of course, the other motivating factor was that the economy went to shit. People were hungry and tired of waiting in long queues with shelves at the stores almost empty. Nothing to do with "discussions and political institutions the elites were working in" though.
You are totally fundamentally wrong. You are disagreeing with most scholarship on how revolutions happen in political science.
Hope doesn't work if there are tanks who shoot at you. The people in Poland were not braver then those in China or those in Hungary. The difference is that in those cases the political system had the will to oppose them with the force required.
Unarmed protestors simple can not win against an army. Its pure idealism to believe that.
The protesters in late 1980 might have been larger and more popular, but if the Soviet unreleased it might, it would not have mattered.