Many times on this site there have been stories of people that did just about everything wrong and survived. So, surviving does not mean they are experienced and savvy. Surviving is often due to the help of others or pure chance.

Yes, he did some things right, but what did he do wrong?

Granted, he couldn't carry his backpack in his condition, but he could have dragged it on a cord. Or, at the very least taken the food from the pack (he said he was without food).

He said he had no medical supplies.

He had no method of signaling--no PLB, no mirror, no orange tarp, no smoke flares.

Most experienced and knowledgeable hikers would not go on a multi-day trip without those things. I don't even go on a day hike without them--food, first-aid kit, and signaling device (plus the rest of the ten essentials). If you hike alone and off-trail, these things are even more critical.