Hangovers get worse the longer you've been a drinker, rather than an age thing.
People think it's age related because most people start drinking when young and it progresses.
Problem drinkers are more susceptible to kindling as they drink heavier, more frequently and for longer than regular drinkers.
Some regular drinkers would also experience kindling, it isn't unique to alcoholics. The difference is, they don't drink to excess so often and rarely experience the ill effects. Also, because many normal drinkers don't like hangovers, they won't get black out drunk like we do.
Also, bear in mind many problem drinkers end up problem drinkers as they have an existing sensitivity or susceptibility to mental illness, whether that is depression or anxiety, even at a small level. Alcohol will cerebrate or bring to the surface these mental issues, leading to self medication and alcohol abuse.
That said I am sure there are a certain section of society who do not experience hangovers the way alcoholics do, I have a friend who could drink me under the table and the next day he was absolutely fine, whilst I would be in living hell. It's like he is immune.