Didn't they come that way? It's not like they secretly snuck into your house and changed your computer. They sold something broken. It's the difference between going to your house and breaking the latch on your window, vs selling you a window that won't latch.
Adware is not a broken product, it is an illegal scheme to earn profit on other peoples hardware by deliberate deception.
Did they inform their customers in advertisements, in the stores, or in any way that sold devices was being used by Lenovo after sale? Were there a meeting of minds where customers agreed to have their traffic MiTM and have advertisement of Lenovo choice on their device in return for fair compensation? That could have made it legal, but as it stand, no aspects of consumer protection laws, advertisement laws, contract laws, computer crime laws, or data protection laws seemed to have be followed.
They secretly snuck into peoples private property, used a backdoor, and earned profits doing so. They didn't tell anyone for obvious reasons. Had it been a one-man company doing this, then that person would be facing jail time.
Lenovo actively circumvented your security and sold access to your computer to Superfish. If you want to compare it to windows, it's like a security door salesman who sells extra keys to organized crime on the side.
