Poverty of the population? Russia is not the richest country but is not poorest one.

I've seen no indication poverty stricken rural areas aren't where they get a majority of their recruits

This poverty pattern reflects the Kremlin’s recruitment strategy. After the unpopular September 2022 mobilization of 300,000 men, the authorities pivoted to “voluntary” recruitment with high salaries and large one-off bonuses.

Polls suggest that a majority of Russians believe new soldiers are driven mainly by money. Casualty data support this: among voluntary recruits, the worst-hit group is men aged 45–50 — people more likely to be under financial strain. Many regions with high sign-up bonuses, like oil-rich Yugra, are ready to enlist volunteers from neighboring districts, and even reimburse travel expenses.

https://cepa.org/article/death-without-glory-russias-message-to-the-frontline-soldier/

If you see the videos of them using "soldiers" with mental and physical disabilities it shows they're recruiting just about anyone