Why not? The quality is good enough that millions of people around the world are using it in their house right now, profitably for Ikea. I'd say that's a very good definition of quality to imitated.
Exactly. I wouldn't dance on most of it but it serves its purpose quite adequately. I find that IKEA has consistently good quality. Very little of there stuff is great quality, but almost nothing is of a low quality. It is all adequate at a very reasonable price.
I agree that if you are expecting top quality you will be disappointed. But for the price it is hard to find much of better quality. Especially not so consistently.
Which reminds me - and it's not IKEA-specific: I wonder how many people got severely injured or lost their lives due to a desk or wardrobe collapsing under them when they stood on it, unaware that these days, desks and other waist-level flat furniture often aren't designed to hold the weight of an adult human? When I grew up, standing on furniture was a normal thing - these days, I'm very careful about even leaning on it.