There's more and more research that says you do need to do some sort of resistance/strength training to minimize morbidity and mortality. It doesn't have to be weight lifting, but if you're only doing cardio you're missing something.
Up until around age 60, your body adjusts your muscle mass based on usage. Somewhere around 60, you start losing muscle mass. If you have just enough muscle for day to day activities in a sedentary life at that point, then over time daily tasks like carrying groceries or standing up out of a chair are going to become prohibitively difficult. You need to do something that encourages your body to grow more muscle than you need for day to day life so that you can afford to lose some of it.
Most people did manual labor. Even if they didn't, everyone walked more, or rode horses, chopped wood, drew water from wells, and did a hundred other things that required using their muscles in a way that's just not necessary today.
> my strength training is rock climbing
That's weight lifting too. Bodyweight is still weight.
The weight training craze is far, far more recent than our shift to a sedentary lifestyle.
The comment you responded to about not "min maxing" https://news.ycombinator.com/item?id=46499625 only advocated resistance and strength training, not "weight training" specifically. It's hard to dispute that having a stronger body is better for living a healthy life.
None of that will bulk you like weight lifting nor is similar to weight lifting. Those guys were smaller. By our standards, they would do a lot of low resistance repetition, basically.
> That's weight lifting too. Bodyweight is still weight.
I mean, you are stretching the definition of weight lifting to unrecognizable. Climbing is not weight lifting anymore then walking is running.
Even weight lifting won't bulk you unless you actively try to bulk. Seriously, appearing muscular or bulky when you're fully dressed is actually quite hard to accomplish for most people (practically all females and maybe half the males). It takes years and years of gym work and diet that most people won't ever put in.