Where are they going to put their air defence? They relocated many of the few Patriots they had towards trying to stem the rout at Avdiivka. I think two or three got destroyed in transit. A couple more were Iskandered, I believe.
Currently, senior Uke leadership is on the run. Nowhere in the country is safe from a hypersonic. The troops and front line fortifications are FABed with impunity. The entire electric power generation system is rapidly being degraded to functionally dead. I assume the bridges are next. Where is their air defence?
The SAM situation can be resolved overnight. The US just has to fly in a bunch of Patriot missiles from their Euro stocks.
Will the US do that? Lets see.
Your other points are sheer catastrophizing. The Russians are (still) incapable of breaking through, or of operational maneuver.