The word “legacy” is often used to refer to products that are dominant today but threatened by disruptive influences. Legacy airlines, for example, are today’s largest carriers but ones burdened with aircraft bought earlier and with labor contracts negotiated years ago. Legacy connotes power, but also vulnerability.
The same logic can be applied to general aviation. Cessna and Piper are certainly legacy manufacturers. Decades back both become larger corporations increasingly distant from the original work of Clyde Cessna or William Piper. Others have already succumbed to market forces or have materially changed. Think of Beechcraft or Mooney. Both are quite different organizations from what Walter Beech and Al Mooney once created.
All this reflects normal developments that happen over time. Legacies can be good, even great, but one fact is true: Legacy cannot stand still.