Without questioning if seizing the property of Russian billionaires is justified or not, if you believe in equity, the property of American billionaires should also be seized by the other countries for the nearly 200 000 civilian deaths in Iraq (which is much worse, but the US-led war lasted longer). Source: https://en.wikipedia.org/wiki/Casualties_of_the_Iraq_War#Ira...
Putting aside the confiscation question, it’s morally obtuse to liken Iraqi civilian deaths, the top cause of which per that link was execution after capture by insurgent & other non-US-aligned forces, with Ukrainian deaths from indiscriminate Russian shelling of civilian neighborhoods.
By the Iraq War Bodycount's dataset, the civilian kill count of US forces alone, without including the Iraqi government forces, almost matches that of the sectarian terrorists who explicitly sought out to kill civilians. From occupation to leaving in 2011, it is only about 20% less. That is plainly unacceptable and criminal in any context.
https://www.theguardian.com/commentisfree/2010/oct/25/iraq-t...
https://www.theguardian.com/world/2010/oct/24/iraq-war-logs-...
https://www.thebureauinvestigates.com/stories/2010-03-10/oba...
https://www.thebureauinvestigates.com/stories/2011-05-23/us-...
https://www.thenation.com/article/archive/iraqs-new-death-sq...