It almost sounds like it's being implied that strength training will eventually hurt you, and especially if you're a little wiser in your years. If that's what's being said then I respectfully disagree.
There's an issue of semantics, though - what do we mean by "heavy weights" ?
Also, we all have an expiry date, and all of our joints are wearing and tearing regardless of whether we decide to powerlift, do yoga or become a Call of Duty fanatic. There's nothing convincing out there to show that by NOT doing what you want to do, you actually save yourself in any way.
Also worth mentioning - the link between "wear and tear"/degeneration, as confirmed by x-rays and MRI scans is extremely weak. People in pain can have no visible degeneration and people with confirmed degenerative changes can have no pain or history of pain. The argument that we will eventually break if we keep getting stronger is based on the assumption that degeneration = pain/injury, which is actually far from true. And the more research is done on this, the weaker the correlation seems to be.
The strongest guys in the world tend to "peak" in their mid 40's.
I've trained quite a few people in the 40 to mid 60's range with limited (if any) training experience, and they all got significantly stronger with one of the primary goals to feel better (in most cases they came to me because they suffered from some kind of pain). The increased strength in these cases made them "healthier".
With that being said, maybe there is a "point of no return" and, even with great technique and a smart training program, your joints have a structural limit before they start complaining. Truth is we don't know the answer to this. The human body is constantly being pushed to new levels of performance. All you can do is form your own opinion and guesstimate.
Personally, i'm very optimistic about what the human body is capable of. My mindset is just like that anyway but the feeling is stronger since being able to train people.
Resistance training is the foundation of modern physiotherapy/physical therapy.
Prof Stuart McGill has often said for optimal health, we need the right amount of activity, not too much, not too little.
Here's how I often respond to questions like, "but, doesn't that put a lot of stress on your lower back?".
Yes! It does, that's exactly what I want. If we don't inflict stress on our joints they have no reason to be strong. Too much stress is when things go wrong. One of the worse things you can do for your body is NOT stress it. We are always adapting and adapting to nothing makes us weak and fragile. The trick, if optimal health is the primary goal, is finding that balance - just enough stress to cause a positive adaptation, rather than too much stress which can cause problems.
When it comes to training there's just too many variables to give a black and white answer. For example, I know I definitely can't get away with a lot of the stupid stuff I did in my early 20's. Now in my late 20's and I want to say I don't get away with it but, the truth is I just train smarter. For me the injuries came within the first 2-3 years of training. However I handle heavier loads now than I ever have, more regularly, and feel "healthier" than I have in years. I got obsessed with strength training as a side effect of fixing my own injuries - I was hurt before I got strong and started training the way I do now. If the "heavy lifting" was the problem I don't think this would be possible. I have a labral fraying in atleast one shoulder, had a partial thickenss RC tear in one, tore a hamstring tendon, have a torn left knee cartilage, have also tore my groin/adductor, had a few back strains, ruptured ankle ligaments. I got most of these when I was signifantly weaker than I am now, and again I'm stronger and healthier now even with all the heavy lifting...
I agree with Matt on technique and would also comment on intensity. Take deadlift for example, the majority of people training the deadlift use poor form and go far too heavy far too often. Since I started to compete I know loads of powerlifters now and I know the majority of them "train" like they compete (heavy and messy).
Although i've done this myself, using strength athletes/competitors as part of an argument both for or against strength training isn't the best way to look at things. Athletes compete, those who compete make sacrifices for the sake of competition. They will take more risk. So we come back again to goals - what are you training for?
As for the original question - you can "get away with" a lot more with isolation exercises if safety is the concern because there's a lot less that can go wrong. However in compound movements a lot more can wrong a lot easier. You can lift beyond technical proficiency i.e. you can still squat if your knees are caving in and still deadlift if your lower back is rounding. With compound movements you need to be a technician. Stop at "technical failure". It's easier to lift beyond technical failure with heavier weights at low reps, but also lighter weights with higher reps. However, if you comply to the "technical failure" mindset then you can do any number of reps!
I actually find it easier to train clients deadlifts in the 2-5 range, things are a lot nicer. But then again I use singles, too. But a single isn't a 1RM. Singles with 90% shouldn't be messy. I regularly use 50-70% with myself, training partners, and clients for singles doubles and triples - of course they won't be messy, light weight AND low percentages. The devils in the details, too much to consider to say "do this rep range for this exercise, avoid this rep range for these exercises".