I don't know if I exactly follow the analogy, but engines are not binned like CPU's. If you have questions about if you're "on your own" with mods, check with whoever has your warranty and insurance. It might be different car to car or even state to state. Likely, you can get some work done at a dealership that won't void your warranty and tune to a level that doesn't affect your insurance.

> Could the "detuning" rather be interpreted as akin to the "binning" that CPU manufacturers do?

No, it is typically for emissions and fuel economy purposes. Engines are pretty consistent in specs when they come off the line.

The short answer is no. OEMs don't really do quality control tiers. They'll do new vs service tolerances and that's about it.

I don't think the analogy works because you're not getting different hardware, just different mixtures of fuel/air/timing that trade reliability and mpg for more performance.