To speak of 1989 and say "everything changed despite them" is a severe glossing over of the situation. If Gorbachev had wanted to stop those changes, there is no doubt that he could have done so. Repeatedly, some elements in the old elites made moves to hold their worlds together, and other elements stopped them. Did "grassroots organizing and civil society" matter? I'm sure they did. Were they sufficient in themselves? Not a chance. Would something similar have happened again eventually? Perhaps, but that's only speculation.
To speak of 1989 and say "everything changed despite them" is a severe glossing over of the situation. If Gorbachev had wanted to stop those changes, there is no doubt that he could have done so. Repeatedly, some elements in the old elites made moves to hold their worlds together, and other elements stopped them. Did "grassroots organizing and civil society" matter? I'm sure they did. Were they sufficient in themselves? Not a chance. Would something similar have happened again eventually? Perhaps, but that's only speculation.