I believe there's a 2nd aspect to your 80/20 theory--Chinese factory bankruptcies. The CCP harsh lockdown response to Covid put many small factories out of business. The kind that would make 50-cent corkscrews. Add to that reduced global demand because 1) people had stocked up due to supply chain disruptions and 2) we're beginning a recession.

Therefore, I suspect Lidl could get a corkscrew from a large factory but the price would be high and margin low. So it doesn't bother because of your 80/20 rule.

Between 1990 and 2017 however stores could buy cheap goods from China, cheap enough, to spend little on inventory and have a healthy margin.

This is part of the "unseen" inflation everyone recognizes but the government ;)