>they'd be gambling that NATO doesn't launch things into Russia
The official discourse in Russia is that NATO is already helping Ukraine launch things into Russia. So there's no gamble; for them, it's already a fact. Except, currently, it's just a proxy war where Ukraine has to jump through hoops to get military aid and targets approved, and it can only fire from Ukraine's territory. With a direct confrontation, there's no doubt that far more would be launched into Russia.
The official discourse in Russia is that NATO is already helping Ukraine launch things into Russia. So there's no gamble; for them, it's already a fact. Except, currently, it's just a proxy war where Ukraine has to jump through hoops to get military aid and targets approved, and it can only fire from Ukraine's territory. With a direct confrontation, there's no doubt that far more would be launched into Russia.