I used to discuss things like this with a communist friend (in Jr High, eh?).
"USSR had 100 tank divisions in 1945! They didn't need lend-lease."
"And how does that help them survive 1943? Or even 1944?"
"Because... reasons!"

Canada sent a ton of LL to Russia. Those trucks were invaluable, and even the crappy Valentine tanks were used everywhere. Russia had plenty of manpower but little mechanical weapons until 1944. Oh they made a ton too! And they promptly lost them, but no matter there was more on the way.