It is a term coined by local ustaads. The legitimacy to it is that most vehicles don't have structural strength and their drive train does not have a torque rating high enough to safely absorb the energy of the oversize engine.
In light of the post question:
Three things matter for a vehicle.
Root of all above, how efficiently can the power be delivered to the pavement, dirt or any other form.
Most vehicles are designed around a certain power criteria. Therefore their structural elements are built according to that rating. Static friction is a very little discussed force when ustaads are fabricating a vehicle and countless others.
The point being, for example take a Suzuki Potohar and put a V8 in it with a bit of cut and weld. But can the frame and the body resist 400nms + torque to deliver it to the transmission. Can the transmission handle that torque with out shearing gears? Is the prop shaft hardness scale high enough to resist twisting into a jelly bear? can the diffs pinion and crown safely transmit torque to the wheels without disintegrating?
There are countless other questions in dire need of answers or solutions but we rarely give them a thought when tunneling through the thought of channeling maximum power to the wheels.
Our society is very much used to running Japanese vehicles. Japanese vehicles are built with a certain sense of dedication and the Japanese as being one the world renowned experts in steel manufacturing. Makes their metal much more resilient to additional energy being put through them but that doesn't mean its unbreakable.
It is a complex matrix to which most have no answers but rather very vivid opinions.
Just my 2 cents.