You’re confusing cylinder count with displacement. A 4.0L V8 will not make 33% more power than a 4.0 V6. You also fail to understand the concept of efficiency; if you can get the same desired power and torque out of a smaller engine, you improve efficiency and fuel economy under all operating conditions except maximum power output, which will be the same between both engines. No production engine will ever be at 100% of it’s power output capability, so the displacement argument is irrelevant.
You’re not taking engine design into account. In fact, I believe you were the one that made the ridiculous statement that “all V6s are the same”, which is comical at best. As engine displacement has decreased to improve efficiency, designs have become more robust to accommodate the additional power and torque output. The Ford Nano is a great example with it’s CGI block (same as 6.7 Powerstroke), engine block skirt stiffener, variable displacement oil pump, and oil cooler pistons.
You continue to confuse your opinion with the facts. Refer to above. By your reasoning, a soft cam 305 is “better” than a GNX 3.8 Turbo. Do you realize how ridiculous you sound? Not everything is black and white guy, you should really try being open to understanding new concepts instead of living in your own ignorance.