All that is probably true, but what we are discussing here is perceived value to an employer. Its rather obvious in software that perceived value does not accru

All that is probably true, but what we are discussing here is perceived value to an employer. Its rather obvious in software that perceived value does not accrue with experience as it does in fields like law or medicine. Even though data shows doctors get worse over time, a 25 year veteran is held in much higher regard than a 5 year practicioner. In software circles, you are far more likely to be looked at as old and out of date, regardless of the skills you have amassed.