The worst part, I see no reason for Russians to restrain themselves, more damage to Ukraine and Europe = better for them. All they need to do is to wait until the winds will go West.
Every time they've done something major, it has been rapidly followed by serious increases in the level of foreign aid - since the dam burst, cluster munitions (valuable as much because the US has fucktons in storage as for their actual effect), jet fighters, and ATACMS missiles went from "almost certainly not, at least no time soon" to "almost certain, timetable's a bit in the air". This would be a risk even if multiple major actors hadn't started publicly urging for
direct intervention in the event of a power plant breach. If Russia believes
that threat is real, that even limited direct intervention is possible it is a nightmare thought - any of the second tier air forces in NATO (the Royal Air Force, the French Air Force, the Luftwaffe, or the United States Navy's Army's Air Force) has enough combat power to radically change the calculus of this war.