The answer is quite simple-look at the aircraft profile page-this B747 is one of Boeing's Experimental classed aircraft. They cannot economically be upgraded to a production standard. An Experimental class aircraft cannot be used for hire, and converting it to a production standard could be either impossible or prohibitively expensive, and would require reclassification by the FAA, which might not be even possible. This destruction is probably chalked up to R&D costs, and the aircraft has considerable scrap value to Boeing, paid by the scrapper.
The B747s first were put in airline service in early 1970. My wife and I had a round trip flight in one to Hawaii in April, 1970, and the PAN-AM plane stilled smelled new.
In a similar vein, many US military aircraft in our boneyards are now being scrapped for the scrap value, and the contract requires no metal pieces larger than 4" by 4" after destruction. The intent is: no aircraft can ever be restored from the pieces.
When I worked in Flight Test Division for 13 years at Point Mugu, we had as many as 27 USN aircraft at a time that were all so highly modified for air-launched missile T&E they could not be restored to fleet squadron use. Each were, in a sense, one of a kinds. We had one joint program with the USAF called IFPDAS in the 1970s and they couldn't understand what our NF-4J Phantom was, until the N prefix was explained. We sent the USAF data tapes for further data reduction and the N in NF-4J was an initial mystery to them. I should clarify the prefix N, a modified mission symbol, means Special test, permanent. This covers major alterations to test aircraft that preclude their ever being returned to original specifications.