I think this argument is going a little extreme. The guy said it was his opinion of what he calls a generation change.
I don't really care, but most people call a Major body change a generation change, but I would be somewhat prone to call a car that has the same body style, completely different motor a new generation. I don't think that there is a concrete definition of what a merits a generation in cars. If there is, someone post it, and the source of the definition.
Now if it was the same motor, and got minor modifications, I wouldn't call it a new generation, but if it was moved from like a 2.0 to a 2.2 motor--that would be a grey area, and if someone wanted to call it a new generation, what's the biggie. But no reason to get all huffy and puffy about it.
Do the factories term them like that? Cause if they do--I'd go by the factory "named" generation.