In short: words change meaning. Addition as a term includes a history of positive definition in the 17th century of "devoting oneself to another person, cause or pursuit", to being "associated with excessive alcohol use" in the early 1900s, to "linked almost exclusively to excessive patterns of substance use" in the 1980s, to the modern medical definition—not made until 2013!—of "the most severe degree of the addictive disorders, due to pervasive/excessive substance-use or behavioural compulsions/impulses".
Indeed, for most of the late 20th century, no one could agree what it referred to! "The word addiction was deliberately omitted from four consecutive editions of the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders [...] because it was considered a layman’s rather than a scientific term, pejorative, stigmatizing, and too difficult to define. There were simply ‘too many meanings’ (Alexander & Schweighofer 1988); the term lacked any ‘universally agreed upon definition’ (Buchman et al. 2011); the result of using it was ‘conceptual chaos’ (Shaffer 1986, 1997)."
So it hasn't been redefined to mean anything because it was never fully defined to begin with. Only in the last decade has it truly been formalized, and yes includes both chemical and behavioral dependency.
[1] https://www.tandfonline.com/doi/full/10.1080/16066359.2018.1... [2] https://www.tn.gov/content/dam/tn/mentalhealth/documents/FIN...
Addiction does not exclusively refer to chemical dependency.
> Now it is being redefined to mean “people doing anything I don’t like and don’t think they should do”.
I don't know where you got that impression, if that were the case then I would expect there to be widespread disagreement about what is addictive. Why is it not possible that both dependency and addictive substances are often harmful?
> Whatever you call it there is a tremendous difference in type between alcoholism or opioid dependency and social media use.
What does difference in type mean? Are we distinguishing between alcoholism and opioid dependency or between material conditions and it's presentation in social media?
> Calling them the same word is grossly misleading if not outright lying.
They do share quite a few characteristics.
The word is used for deleterious behaviors that have become compulsive or the person has otherwise lost the ability to control.
"Deleterious" may depend on the person and their life circumstances. And inasmuch as "lost ability to control" relates to "willpower" -- or shall we say various executive functions -- it may be difficult for someone without those problems or limitations to understand. That doesn't mean it isn't real.
The modern world has become much more complex and the traps for our primate brains have increased. Our understanding of psychology also continues to deepen and better understand the problems.