Definitely don’t agree with this at all. Go sit in a VW then sit in an Audi, or Toyota/Lexus, Hyundai/Genesis and tell me they are of the same quality. They are not.
They didn't say luxury is all marketing (ergo, the "if"); they said scoping your car as a luxury product while it's not devalues the meaning.
They then provided a specific example and pointed out that most products they've bought/researched from China (so, completely anecdotal) seem to be of lower quality.
Depends on how you define quality. A car that feels nice to sit on and drive may not be the most reliable way to get you from point A to point B consistently. The reliability of many (at least older) Toyota models is impressive, while German reliability has been mostly a myth in the 2000's.
Audi, Lexus, and Genesis are the luxury brands for their respective manufacturer. I think they’re saying that the cars sold under those brands are noticeably better quality than the VW, Toyota, and Hyundai branded cars.
They then provided a specific example and pointed out that most products they've bought/researched from China (so, completely anecdotal) seem to be of lower quality.