You are very mistaken here. Russian army is extremely dependent on manpower.
While Western armies have pursued heavy automation and optimization because they have shrunk and professionalized, the Russian army remains a conscript army. There were reforms to professionalize and imitate the West, but they were never finished. The Russian army remains largely conscript-based. (That's why there were these sham annexations referenda. A way for Putin to give himself the right to send conscripts outside of Russia, something that is not supposed to happen outside of a formal state of war. Legally, this is still "a special military operation"...)
A simple example is ammunition logistics. With small armies (at least compared to their Cold War size), the West couldn't afford to throw the same kinds of volume of ordnance as they could during WW1 and WW2. Hence the focus on precision: instead of launching a hundred shells and hoping one of them will hit the target, let's throw just one, but one that's guaranteed to hit. It's much more expensive -- maybe a hundred times more expensive, even -- but you get the same effect and it's just one hundredth of the logistics weight, you therefore need less ammunition, less canons, and less personnel. Likewise, logistics were improved to go faster. Palettization was a big thing, allowing to expedite tremendously any sort of transfer from boat to train to airplane to truck -- just a lot faster with less work and less workers. Russians? No such thing happened. Everything is done manually. Transferring ammo boxes from a train to a truck takes hours as each box must be moved by hand individually.
Russia didn't push for the same level of automation because they've got conscripts, so who cares? Workforce is abundant. The entire structure of the Russian armed forces is built around the idea that they have a ton of cheap human labor. Conscripts account for 30% of each BTG, that's the official proportion, without the conscripts a BTG is only at 70% strength, it's how the whole thing has been designed.