PPP is the exchange rate normalized cost of a basket of goods in different countries. The way you have a high PPP is by having an economy where people can buy a lot with a little. Whether that lot happens to be eggs, steel, or artillery shells. The US is avoiding a hot war with Russia over Ukraine. They will never, ever, engage in a hot war with China over Taiwan. They'll feed weapons to Taiwan and let the Taiwanese fight to the last man, somehow try to frame the eventual defeat as a victory, wash our hands of it, and rapidly move on to the next war.
And if you think Russia is failing, then I'm not sure you know what victory looks like when fighting a competent adversary. The Ukrainian army is being fueled by endless and increasingly brutal forced conscription, and backed by Western weapons, tech, hardware, and intelligence. But instead of the present, let's go 4 years back after the invasion and when the West decided to get overtly involved. Imagine I came to you and said 'hey stickfigure not only with this war last for years, but in 4 years Russia will have the strategic initiative, control a massive chunk of Ukraine, and be continuing to push forward' -- what do you think you would have said? 'Russia must be failing' wouldn't really be a logical response then, or now.