It takes a lot of time to get better, specifically if getting better involves changing major parts of one's lifestyle. When it comes to recovery from a high risk lifestyle, I tend to put more hope in younger people, simply because they have the time to work their stuff out. Yet, that doesn't doom anybody over 40, because we can all work at different speeds. I have seen people give up a lot of nasty habits overnight, and the recovery rate seems to reflect the serious nature of these folks. I, for example, started recovering from street life and drug use at 20, but I did not show up in university until I was 26. A 47-year-old friend I met gave up everything but smoking and showed up at the same school two years after his sudden lifestyle change. Not that post secondary education should be used as a ruler for success, but it does speak a lot about choice. Sure, young people have the advantage of time, but they take things less seriously, and consequently are taken less seriously. As Oscar Wilde once said "Youth is wasted on the young."
The further advantage of older recovering people is the level of experience they offer to new people in recovery. Somebody finally waking up at 53 can find some real hope in talking to a 60 year-old person who changed their life at 55. It can be daunting and humiliating for an older person to be facing an AA meeting full of young people, and it is a relief I'm sure to see others in the crowd they can relate to.
In any case, I have seen some amazing people do some amazing things when they have the fire of their own mortality chasing them. It is never too late.