Psychological addiction isn't controversial at all .It's quite well established that it both occurs and affects different people in different ways and to different degrees. The difficulty -because it's subjective- is putting numbers on it.
You appear to be coming from the "Well I don't feel it, so they must be whining pansies" school of thought. Video games are addictive; and are deliberately designed to be so...and it's not purely psychological either...you get regular endorphin and other feel-good jolts supplied by your own body at regular intervals. And why stop at writing off video games and caffeine withdrawal? PSTD, depression, and grief are all only in people's heads, so why don't they just sack up and stop moaning about it, huh?
It isn't only about physical dependence...people get addicted to the rituals around their habit...psychologists call it reinforcing. Faffing around with filters and suchlike and the act of drinking it for coffee; (in my case) rolling the cigarette, raising it to your mouth, the inhale etc. These behaviours are repeated many times per day and can become as difficult to get rid of -if not more so for some people- as the physical dependence itself.
That's why vaping works for very, very many more people than nicotine patches. Basically there's enough stuff to fiddle with to re-route all these ritual behaviours into something considerably less harmful; with nearly no stress at all.