You are absolutely right, sanctions will not stop Putin, they did not stop him before, they will not stop him now or in the future. we are all adults and we understand that ordinary people feel sanctions most of all. Their goal is to remove Putin by the hands of local residents, the mass population, or with the help of a disgruntled elite.
But it won't work, it will only lead to the emergence of another Iran. But stopping Putin through war will worsen the lives of citizens in all participating countries, that's why it will not be. The world is trying to solve Putin's problem so far at the cost of the comfort of two nations.