I doubt Russia has the ability to take out thousands of Starlink satellites.
They don’t have to. Colliding with one satellite in a shell will massively disrupt activity in that shell for months, if not years. The whole thing doesn't even have to go Kessler either. A number of well placed debris clouds will send satellites scrambling; a bad actor simply needs to keep up with disruption and stay ahead of the scramble, not with the starlink launch rate. 1 in 100 is probably more than enough of a kill ratio.
Obviously the world will get real miffed long before Vlad hucks up his second kinetic let alone his 40th so this is all kind of academic anyway...but...no...to achieve the goal there's no need to kill anywhere near every satellite.