Russian tanks and other equipment cannot be easily replaced under sanctions as the production is dependent on the US, German, and South Korean parts. Putin just issued an order to convert their military equipment production to models from the 1960s to use domestic,
Soviet technology. But this will take time for re-tooling, re-training, getting the right crews, etc. This is another fucked up idea by our chess
genius, comrade Putin.
How desperate are you if you hope that Putin will run out of tanks. Now, in military chronicles from the Russian side, they mainly show Soviet T-72s (with a modernized cannon that pierces even older Ukrainian T-60s through the forehead), which are stored in factory solid oil in warehouses, tens of thousands of units, as a legacy from the USSR . Where are the modern Armata tanks, or at least the T-90? They are simply not necessary within the framework of the model of warfare used in Ukraine in the conditions of complete Russian dominance in the air.Soviet technology. But this will take time for re-tooling, re-training, getting the right crews, etc. This is another fucked up idea by our chess
genius, comrade Putin.
I think the US just found the perfect way to ruin the Soviets once and for all.
I hope this will not happen too quickly, otherwise the cavalry division of the fighting Buryats has not yet jumped up from the remote taiga to look at the Ukrainian asphalt and electric street lighting for the first time in their lives. 
It is funny to hear people talking about Putin's army in those terms... the T-90, which is awesome, yet costs a fortune has a very limited production (and only requires 1 cheap Javelin to destroy of which there are 15000 in Ukraine as of now), Putin's air forces which are said to be awesome... yet absent and scared to fly over Ukraine due to the air defences and, again, expensive and unreplaceable,... It seems that Putin's strategy is to scare Ukraine by talking about how big the army is, without actually being able to field it, supply it and use it to any degree of effectiveness except where they have 20 to 1 superiority and at the cost of many young Russian soldiers dying.
But the special tragic comedy price falls onto the "stored T-72s" argument. Do you think that you just leave a tank there and then, after 20 years, you turn the key and it works? Do you think Putin u can do a better job at supplying these than he is doing now with the troops he has? Do you think their crews will feel safe and willing to enter into combat in a tank that can be put our of service even with a well thrown Molotov?
Yes, in theory Putin's walk-in close is full of robes and dresses, yet these do not seem to be anywhere to be seen. Who will tell the emperor that he is naked?