Didn't independent analysis show that they had awful LODs and such on release, causing massive performance loss? Maybe Unity was supposed to automagically take care of that, but if it didn't work, doing the work manually was always an option. They just chose not to.
If your game's broke, don't release it. That's like a carpenter blaming his tools for a slanted kitchen cabinet. I don't care if your saw blade had a manufacturing defect, take it back and fix it!
It'd be a case study in what not to do if publishers didn't make that same mistake over and over again. There is such a thing as unacceptably poor performance and fixing it cannot possibly be more expensive than lost sales revenue.