Avalon/ES350, 370Z/G37, Pathfinder/JLX, Genesis/Equus, US Accord/TL, Euro Accord/TSX, etc. Same platforms, same engines, different sheetmetal and different interiors. It's only a problem when GM does it.
Avalon and ES350 - two totally different beasts. Designed from the ground up by two independent teams with Lexus actually built in Japan. Using the same powertrain is not a sin. They ended up very similar which is reflected in price (unlike GM).
Same with Genesis/Equus. There is more than just interior difference - Hyundai applies a completely different philosophy to the entire concept of Equus ownership.
US Accord and TL? Seriously?
Euro Accord/TSX - two variations of the same car offered for different markets with different expectations. Not offered side-by side. Honda realized its mistakes of late with the TSX so it's gone. And there won't be any Eurpean/US Accord anymore, same car for both markets. At least they show they can learn.
You were saying?
I'm saying that the distinctions you are trying to make are ephemeral at best and completely disingenuous at worst.
The Lexus ES can still be optioned up to be more expensive than the Avalon ($52k vs $42k), even thought there is significant price overlap.
Regardless of the ownership philosophy red herring, the Genesis and Equus are two versions of the same platform, one being more upscale than the other, the same as the other examples I gave.
The Trax and Encore were designed by two different teams from the same platform. The Encore is offered as the Opel Mokka in Europe. Most of its design and tuning was done by Opel. Most the design work on the Trax was done by GM Korea.
They are offered side by side in the Canadian market because of the dealership situation here. GM has Buick/GMC and Chevrolet/Cadillac dealers. Both need a small CUV, so it made sense to offer both. Things are different in the US, where they get the Encore, but not the Trax. I believe the situation is similar in China. In Europe, they offer the Mokka, and the Trax, but there are relatively few Chevrolet dealers, so there isn't as much overlap.