Pretty much all the discontent you see under capitalism is a result of contradictions within the system. Even the discontent of the bourgeoisie is discontent with the system not catering to their interests as much as they would like (otherwise there would be revolution).

Communism is the movement to resolve those contradictions. Discontent with the system under communism is a sign that we are doing something wrong and should endeavour to fix it. For the generations that have lived life under capitalism, there will be a desire, especially from those who are privileged, to return to the system. This is my view is a result of a lack of education and self-reflection. If these people can be educated out of their hyper-individualism and learn about how the previous system was harmful to many people, it would curb a lot of dissent.

Also, at least some of the dissent will be legitimate grievances caused by bad policies or practices. These people deserve to be listened to, should we wish to avoid the degeneration of the system into some form of class-based bureaucratic authoritarianism, where only some people have political rights and others do not.