Definition of Alcoholic fuzzier? Rubbish. The person putting forward the view that the definition of an alcoholic is now difficult to specify is wrong. This person talks about the wide spectrum of drinkers and how their drinking affects their lives. Some people drink relatively little with a consequential large effect on their lives and visa-versa. This is correct but it has no bearing on how one ascertains whether a person is alcoholic or not.
The only question to ask is whether the alleged alcoholic is unable to control his/her drinking. Is the pull/desire to drink such that she/he has to drink at a certain time or is he able to say "No" and do something else. In short, is he addicted? If, yes he is an alcoholic. That is the definition.
It is likely that an alcoholic drinks a lot before he becomes addicted. It is in fact certain as it takes a long time to train the brain to become addicted.
I really think that this person who is saying these things is just doing it for a bit of PR.