Ukraine didn't even start a lot of conscription until late last summer because they had sufficient volunteers. That also accounts for the higher average age: many of the original volunteers joined the army in 2014 after the last invasion. Now they've lowered the draft age from 27 to 23 to increase the manpower pool and allow more troop rotations off the battlefield.
In WWII, even the US Marine Corps had to resort to getting conscripts for the Pacific War.
You said that they were highly motivated by the prospects of a Western lifestyle and I suggested that their motivation was due to the consequences of not fighting. At any rate, I would like to disassociate myself from press ganging these young men into their untimely deaths if these same people would rather let a few provinces choose separation than forfeit their personal futures. Maybe you feel well justified in insisting on their ultimate sacrifice from halfway around the world to satisfy some unknown principle or desire on your behalf.