They can't listen to what the Russians or saying, for that would destroy their entire premise.

...Mr. Putin’s original plan to take over Kyiv and destroy Ukraine as a nation.

This was never the plan. Putin, Lavrov, and Medvedev have been singing the same song since 2008 if not longer. They view NATO expansion and weapons placements encroaching on their border as an existential threat, and have said as much repeatedly. Imperial realists have said the same since 1991.

The idea that Putin himself wants to take over Ukraine and bring back the USSR is a strawman to beat all strawmen.

But imperialist capital forbid that they listen to the words of their opposition, let alone take them at face value. The expansion of empire must continue unabated.