The usual argument at the bottom of the article "the wealthy will leave" only applies if you let them take their money with them. If you can sanction Russian oligarchs, you can sanction French people who got rich in France and then flee or move their money elsewhere.

And that does not even include the number of rich families who own vast amounts of real estate which they cannot take with them. If the argument is "they'll increase the rent" then implement rent caps (and crack down on fake renters who run AirBnB ops or sublet).