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You mean a smart strength coach. Assuming your joints aren't degraded to the point where they are bone-on-bone, getting stronger with the big compound lifts will help with sore joints. Conditioning, not so much.
Second RJP. Had bad knees and was told not to do heavy load bearing stuff, rehab with leg extension machines etc. After some 5 years there was no improvement, so I cautiously starting squatting below parallel. Now some 10 years later knees are much better, and I'm able to squat some serious weight. When you go below parallel your hamstrings come into play. I think the result for me was building up the muscle both in the front and back of the knee giving better support.
(Yes, talk to your doctor first, just realize they are human too, and make mistakes like the rest of us.)
Due to problems with my right hip, an overuse injury from my karate/kickboxing days, it has been a couple of years since I did any squats and whether or not I do any deadlifts is entirely dependent on how my hip feels. I mainly do machines for lower body work. I recently came across a podcast with Doug Brignole who wrote a book called The Physics of Resistance Excercise. His main ideas are that compound movements, squats/deadlifts/benchpress, may have some benefit but are not the efficient way to build muscle. And, that you don't need to be loading your spine unnecessarily. This piqued my interest in the book since I haven't been able to do those movements for the last few years anyway. https://www.youtube.com/watch?v=8VdX59JGEgQ&t=8286s
I started these late in life - and i had to do bodyweight or bar-only versions while i got back the range of motion to hold the bar on my back and remain stable through the whole lift. Try starting with a pair of dumbells, which are more forgiving to stiff shoulders.
I think they are very beneficial and directly relate to non-athletic daily activities.