Free weights are fine if you use a power rack.
I 100% disagree. As we age there are so many ways we strengthen our bodies for living and two of those are range of motion (flexibility) and balance. There are MANY ways to NOT use machines today and become strong, stretched, and centered. So many I can't even begin to start the discussion here. Except to say. It is best to have proper guidance on free weight use as well as a variety functional training exercises.
A machine can have its use in an overall fitness regime when it comes to injury recovery or just an added focus on general areas (example if a person doesn't want to do real pull ups (or build strength to be able to) then maybe use the pull up assist machine added to an overall program of functional and weight training. There is a lot lost in a variety of ways for anyone by exclusively using machines in a workout regime on a regular basis. But it is better than doing nothing.
If you want to see a lady over 50 with beautiful curves legs, butt, taut, slender abs, and gorgeous youthful lines in her upper, middle, and lower body with wonderful flexibility kick the machines to the curb and pick up real weights and all the amazing functional tools out there in this day and age.