There's certainly a possibility that change will not happen, but this is the best chance we have without escalating it to a world war.
Sanctions on elites have not caused regime change in other authoritarian regimes, we have even less reason to believe that it would happen with this one.
Russian people need to see that they are at a crossroads, and if they don't act in this narrow time window by organizing and protesting by the millions, they may indeed end up like North Korea.