In some (many?) cases, performance is limited on a motor by the ECU because the hardware is unable to cope with the extra wear.
For example same block, heads and intake but different (cheaper) pistons, valves, springs, injectors, etc ... Sure you can easily dial up the power on the cheaper engine to match the expensive one, but at a higher risk of breakdown.
In many cases due to how the supply chain is structured there aren’t any “quality” differences the wear and tear as you’ve mentioned is simply amortized in the cost of the car.
BMW is probably the biggest offender in this regard and you can buy the “unlock cables” for the older (<2015) models
on EBay later they switched to a software lock, which you can also hack.
You can also tell there is no difference in the valves, pistons or pretty much anything else since the part numbers in the service manual are identical.
The only difference in parts comes to the trim and the breaks on some of the models.
That doesn’t unlock extra power out of the car, it tightens up the power steering to give more road feel, changes the shift points and messes with the drive-by-wire throttle sensitivity. Sure it shouldn’t be a paid for feature to you, but I think it should be. If you pay for tightened up steering and more sensitive throttle thinking it is a power increase, that’s your money I guess.
For example same block, heads and intake but different (cheaper) pistons, valves, springs, injectors, etc ... Sure you can easily dial up the power on the cheaper engine to match the expensive one, but at a higher risk of breakdown.