No. You missed my emphasis on commercial real estate. When I mention markets, I'm not referring to a neighborhood, but a city. Class A or B Office space in Lafayette, LA is not the same as those two distinctions in New York City. Those are the differences in market I'm referring to, not neighborhood. Classes do not apply to neighborhoods.
What you described in improvements is exactly what applies in commercial RE. When you add the features and amenities to match Class A properties, you can then rent or sell that property as a Class A asset/property.
All of the class crap aside, you are correct when you understand that a SFR property's value is tied to the neighborhood. The exact same house will have a different value every time you move it on the map. Because the value is based on comparable sold properties within close proximity of the property. This is very important to understand to be able to estimate values with any measure of accuracy.