I think it was kind of the reason. But that statement is also correct. Technically.
With CP2077, they were pushing the Red Engine well beyond what it was supposed to do. Which lead to both, them deciding to switch to Unreal, and causing a bunch of bugs. So the bugs weren’t the reason; They were just another result of the reason.
But they aren’t all made by slave labor. You only have to spend 3-5x as much. Not a problem if you buy %80 less clothes.