Young people have been sold the promise that working hard and getting educated means they can have a nice life. Now that either needs to be fulfilled (cutting corruption, upsetting Russia etc). Or the rest of the country needs to admit it was a lie and watch all the young, educated, hard working people leave for the west.

This isn't specific to Belarus, only the local details (democracy, Russia etc) differentiate it from say Hong Kong or brexit Britian really.