I can refute much of the threat with a simple question:
What possible targets could the Russians bomb?
Ukraine is about 360,000 square miles. Russian nuclear doctrine has long specified attacking *military* targets (though the US targets civilian cities). But unless military targets are “concentrated”, if they are not units, or are not military infrastructure, it’s not worth it to use nukes.
Importantly, the optimal size for any nuke they would use is likely limited to 25-50 kilotons(kt). That’s about the size of the bombs used on Hiroshima and Nagasaki.
Back to area. Those bombs each destroyed all homes in about a 1-1/2 mile area.
Bottom line: Had Russia been willing to use nukes, it’s hard to imagine when in this war they would have been preferable to conventional weapons.
You’re crazy!