I don’t know why you’re being downvoted. What you say is correct and ethical, in my view. Putin and the Russian government are to blame, not random Russian citizens.
I believe the goal of sanctions like this is to make the people mad at their leaders. So you sanction Russian citizens in the hope it'll help motivate them to create change. Not sure it could work with Russia, but maybe?
I don't understand how anyone thinks this can work when the one opposition leader has been poisoned and put in jail.