Not sure I agree with much of that - at 68 I usually get to the gym 3 times a week for 1 hr weights sessions in order to maintain muscle tone and bone density. I don't do massive weight but 2kg....lightweights!
Don't see why we need a high protein diet either - balanced is best...
https://www.theguardian.com/lifeandstyle/shortcuts/2018/dec/04/is-60-the-perfect-age-to-start-lifting-weights