This is just irresponsible. There is a near zero chance that Russians--whether "oligarchs" or otherwise--are going to rise up against Putin. Everyone saw what happened to PMC Wagner's leader Yevgeny Prigozhin, and they're also aware of the oligarchs who fell through 2nd (and higher) story windows and the activists who somehow swallowed radioactive elements that are rarely seen outside a nuclear reactor.
I only said near zero chance because of the Prigozhin example. Otherwise, I'd say a zero chance.
One reason this is irresponsible is that Westerners, weary of hearing about the war, may pin their hopes on a sudden coup ending the war instead of pressing their leaders to give Ukraine the full support it needs to successfully drive the Russian invaders out. Thus, they undermine the cause they intend to support by spreading things created out of their imaginations as though they were truth.