[watchfirst9]

More likely it is for the consumption of Russian ammo, which is many times that of the Ukrainian side.
And Russia is pulling out its old Soviet-era stockpile for this war.

However if the Russian stockpile is depleted (will still take months though) and NATO side starts a war, the bombs used will be nuclear.

Can see Rus using Soviet era stock pile, as they using a lot non smart bombs in this war.
And with the rate at Ukr army losing ammo to Rus, Rus artillery can last many months more.

A real surprise is old T62 which not even in reserve list still in quite good condition.
As Austria commander highlighted, T62 being smaller than modern tanks,
can battle better in narrow city streets.