Mistaken Extrapolation

Not all properties of an object can be extrapolated to an arbitrarily chosen superset. If something is extrapolated beyond its scope, it's a mistaken extrapolation.

Don't you mean generalisation, rather than extrapolation?

• Extrapolation is extending some series of measurements into an area not yet measured.
• Generalisation is applying something from a specific area to a wider area - which fits your definition above)

There are two sides to this coin:

• Fear of extrapolation (SlipperySlope)
• Demanding extrapolation (OneThingAllThings)

See: UnderestimatingSlope