Nice story, but I find it hard to believe that bees could survive on a commercial hive for 8 years left alone. He may have gotten lucky and had a swarm that came along and took up residence in the hive before he got there.
The most I can get out of any of my hives is about 3 years without some form of restocking. Queens fail, mites overtake them, small hive beetles infest them. Comb gets old and needs swapped out.
I am a different kind of beekeeper, I don't feed any supplements. I don't preventive treat the hive with any chemicals. I don't fuss over them much, they are wonderful bugs that have an interesting life. But in life, only the healthy should survive to carry on.
I do split the hives to prevent spring swarms if possible and make new hives from the originals. The removal of a queen breaks a brood cycle and buys them additional time where the mites can't lay eggs and kills them off for a while. I spread mineral salt under the hives to kill the beetle larva when it falls out of the hives to pupate. I keep the hive in good physical shape and the bees dry.
In my 12 years of keeping bees, I have lost many hives. Always a few every year, one time over 2/3rds of them. I have bought 4 hives of bees and been given 1 swarm. I was up to 20 viable hives at the peak, down to none 1 time. I am currently at 6 going into winter, maybe.....