Not familiar with changes in 1996; please share a link.
To my understanding, the ADA protects against discriminatory treatment of individuals with a history of substance use disorder or those in treatment. It doesn't offer protection for active substance use or impaired performance related to the diagnosis.
The ADA doesn’t have an exhaustive list of specific diseases or disorders. Instead, it defines a disability as something that “substantially limits one or more major life activities.”
“Major life activities are those functions that are important to most people’s daily lives. Examples of major life activities are breathing, walking, talking, hearing, seeing, sleeping, caring for one’s self, performing manual tasks, and working. Major life activities also include major bodily functions such as immune system functions, normal cell growth, digestive, bowel, bladder, neurological, brain, respiratory, circulatory, endocrine, and reproductive functions.”
adata.org
What this means is that for one’s substance use to fall under the protection of the ADA, it has to be severe enough to substantially limit perhaps their sleep, their work, their brain function, etc. It is determined on a case-by-case basis.
Says who? It can certainly ruin your life. Some people's brains are literally wired to where they can't stop. The compulsion is overwhelming. I guess you can argue about the terminology.
It's semantics, but ADA protections and supplemental benefits don't apply to gambling disorders.
Which is strange, because gambling addiction is listed in the DSM-V as a mental disorder. There is legal pushback on it, however, so don’t be surprised if this is updated soon.