Eh, I think something might have lost in translation, because I don't think Ukraine has ever been capable of deploying millions of troops, like they probably don't have that many uniforms, not to mention rifles.

I think the Pole is talking about how many men the UA government lost in the sense that they don't know where they are. We know that a couple million fled to Russia, and unlike EU states the Russians aren't likely to share any info with them.

Another thing that gets overlooked is that Ukraine hasn't managed to do a census since 2001. Combine that with their pressganging recruitment tactics and you get a lot of dudes who just threw away their documents and even if they're still in Ukraine, they're working for cash under the table and lying low. There might be a few million dudes who are in the country but the government can't find them - or doesn't even know they exist if they were born after 2001.