Given that a non-trivial percentage of Russian failure modes involve nuclear Armageddon, I don't think we'll see much cyber war on Russian infrastructure beyond the vandalism and petty mischief.
Anonymous hackers probably don't want to start ww3, and there are likely embedded agents keeping an eye on participants to prevent overreach. It's ironic to think that Russian infrastructure is being actively protected by western intelligence to carefully manage the pressures and escalation. Or maybe optimistic...
I think it's established fact that power, water, gas, and communications are fragile and subject to disruption at a moments notice more or less worldwide. Rigorous projections show 90%+ casualty rate in dense urban regions if power gets shut down during winter months. Even without nukes or bullets, cyber war could kill billions.