> If people exercised instead of living in their cars/offices and walking 5 minutes per day

I did that. Running, cycling, walking, etc. Substantially more walking than 5 minutes a day, too...

> instead of having their body give up at 40

...and my right knee became unfixable trash somewhere between 45 and 50 (a variety of ailments, possibly exacerbated by a ~2001 injury.)

I'm sorry for you, and it's a data point, but statistically at 45 virtually everyone is an heavily overweight/obese excuse of a human being. For every sport injured person you have 100 obese who can barely go though basic human movements anymore