Summary
Ukrainian President Volodymyr Zelenskyy stated that enforcing a peace deal with Russia would require at least 200,000 allied troops, emphasizing Europe’s need to strengthen its defenses against Russian aggression.
Speaking at Davos, he called for greater EU investment in military technology and urged NATO membership as Ukraine’s best security guarantee, despite opposition from the U.S., Germany, Hungary, and Slovakia.
Zelenskyy criticized Kremlin demands to shrink Ukraine’s army and warned that if Russia wins in Ukraine, it could threaten other nations.
Attrition will only work if they have the same starting point, but Russia has way more population than Ukraine.
Pure population is not the only factor that determines Russia’s and Ukraine’s success in the war. There are other factors such as economic output, public support, equipment, ammunition, military personnel, international influence, etc.
Right now the personnel limits for Ukraine and Russia aren’t necessarily about each sides’ male population, but over side affects that recruiting soldiers has. Ukraine is reluctant to recruit younger soldiers due to the effect it would have on the country’s future demographics. Russia is reluctant to recruit more soldiers due to the effect that would have on the country’s economy and by extension, war support. In Russia’s case, that led to paying North Korea for mercenaries instead of recruiting more soldiers.
Here are relevant videos on the topic that I recommend:
https://www.youtube.com/watch?v=8tHkwLSS-DE
https://www.youtube.com/watch?v=RiAWQ0h7g-g
https://www.youtube.com/watch?v=vf2vSoWsmgI
https://www.youtube.com/watch?v=TzR8BacYS6U
https://www.youtube.com/watch?v=EHUQmJCa3aY
As it stands right now, the most visible breaking points for each side’s war efforts are possibly the exhaustion of one of these: Ukrainian ammunition, Russian MBTs, and Russian economy.
There are other factors ongoing right now though that also make it less likely for each side to give up if a breaking point is reached, such as Ukraine’s lack of security guarantees, and the Russian economic fallout of ending the wartime economy.
All of these factors could definitely change though if the international climate changes, e.g. the EU gets more political support for the defense of Ukraine, or sanctions are lifted on Russia.