This is a hopeful fiction for several reasons. The first is that, after the Bay of Pigs fiasco, such an uprising among the people is unlikely because they feel failure is inevitable. That leaves us in an uncomfortable position. We can accept the refugees and give up on ever having the desired changes in Cuba, or we can reject them and shoot ourselves in the foot as a nation. Another reason this uprising never will come to pass is other nations don't have this embargo.
European nations have trade with Cuba now and have had it for some time.
So long as they continue to trade with Cuba, the discontent level necessary to cause the desired uprising never will be reached. Another side effect is the darkening perception of the United States held by the Cuban people. The ban gives Castro and his ilk not only reason to point to America as an enemy, but also a degree of validity when they do so. Keeping the ban directly contradicts its original intent, and prevents any chance of American ideals catching on in a big way. Even worse, the ban deteriorates relations between America and other Latin American nations in many ways.