Lets be clear. If someone with osteo arthritis already cycles and wants to continue then my professional advice would have been that provided the joints aren't in an advanced stage of degeneration, i would have said go ahead.
If someone in the same circs wanted to cycle for other reasons (fun, social aspect and so on) I would say give it a try but build up slowly, not too much hilly or rough terrain and stop if you get increased joint pain.
If someone in the same circs has asked me, as the OP did, whether taking up cycling would be beneficial. I would be saying what I have said; that while it is low impact (not jarring like jogging or zumba) it is load bearing and there are better ways to maintain and improve muscle tone and range of motion.