You can ask Earl or Efren on the effects of aging on their pool skills. Efren supposedly said he wouldn't be able to beat the old Efren.
Earl is in his mid 50's and trying to make a living the only way he knows how, by playing pool professionally. Folks here make fun of his cues and the other crutches he wears (weights, headphones, finger splints) rather than look past superficially.
I watched Earl in a match from a few ears ago. He didn't seem to care at all if he won or not. He was soooo good for so long I think he just can not get the fire back. Tiger Woods seems to have the same issue. Marvin Hagler said "it is hard to get up and run in the morning when you are sleeping in silk pajamas". Tiger's problem but not Earl's.