Not really. The conventional war will be between Ukraine and Russia.
If you were Ukrainian Army ( Circa 200k ) - Would you fight a conventional war against the Russians ?
even if Russia manages to somehow 'switch off the whole of Ukraine infrastructure' (which is vanishingly unlikely to be possible).
Why is it vanishingly unlikely to be possible ? - Isn't cyber the next big thing according to Radakin ( Only the UK is probably 20 years behind the curve )