My experience is that every movement pattern causes "injuries" like a sore tendon, wrenched back, inflamed shoulder that surface with every 20 pounds of added weight until I figure out what about my form is incorrect. Usually not something a trainer would see like "don't flare your elbows", internal stuff like "use your glute medius to help push" or "elbows in line with the torso on squats" that might be in 1 of 20 YouTube videos.

I use the weight training to surface the injuries to make me aware of what I'm doing wrong in daily movements. I might finally be past this and able to just go in and push weights but it's taken years. I feel like it's down to the body I'm living in and what I consider a pain threshold, not any risk taking or lack of information.

Only the 80% number was given. If he has been going to the gym for 30 years and had 5 injures at the gym, one outside that would be incredibly low for a total, and that level of carelessness at the gym is lower than I'd expect. If his routine was over 1 month then there are big problems.