Yes. There are currently 39 people on the U.S. Magnitsky list. Their names have been publicly listed on the U.S. Treasury OFAC registry. Their visas have been cancelled and their assets have been frozen.
Most importantly, as of the moment your name goes onto the U.S. Treasury sanctions list, there's no bank in the world that wants to violate U.S. sanctions. They are able to close their accounts for any person on that list. I'm not just saying that about U.S. banks: it's any bank. No bank wants to be in violation of U.S. sanctions.
If you're on that list, you can no longer open a bank account and you can no longer operate a credit card. No international company will do business with you. Effectively, you become a financial pariah in the world. Also, even though this is just about U.S. travel bans, many other countries look at that list and deny visas on the basis of that list, so all of a sudden, your travel opportunities become limited.
Most significantly, we all know, and they all know in Russia, that eventually the Putin regime will fall. The current plan of all the bad guys in Russia is that when the regime falls, they will flee to the west and enjoy their ill-gotten gains in the west. But if you're on that list on a public registry, you can't flee anywhere, because when you flee somewhere and ask for a long-term visa or for asylum and the asylum officer types your name into the computer, he's going to say, “Wait a second. You're not welcome here, and in fact, we're going to send you back to Russia.”
There's nothing so existentially terrifying for a bad guy as not having an escape plan, which is what this does.