Total population is meaningless. The available manpower for its military and how effective it can use them is what matters. Russians are dying at 6:1 ratio vs Ukrainian defenders and is probably getting worse given the lack of IFV and APC for Russia. Throwing 30-40k men away per month for a few square miles is a wasteful and meaningless strategy. Using golf carts in assaults is not something a country 'making bank' would do. Inviting North Korean soldiers to help out is not something a country with plenty of spare bodies would do.
Russia is desperate and its economy is overheating due to a lack of workers. If everything was going so well for Russia, why is their bank rate sitting at 21%?
The deals have already been made. Russian frozen assets are being used.
Russia has already lost. Its just a matter of time before the penny drops.
Maybe Trump will somehow allow them to withdraw from Ukraine without the loss of face.