I go nuts on this subject as I've spent 9 years dealing with rules about gears for kids.
It takes 4-5X as long to build supporting tendons as it does muscle.
You CAN over fatigue tendons. If you are riding too much all of a sudden, then back off a bit. It may be age, but that is not my first guess.
But if you take your time you and I will both have a hard time finding evidence cycling harms knees.
Maybe for women, but I doubt it, and not for men.
I also don't buy higher cadence is better. Higher = more use. More use is typically what leads to fatigue. Inlaw is a USA champ 75+ power lifter with no knee issues and way more force than cyclists. It is not force as much as it is fatigue that causes knee issues.
Ride what you feel like.