In short, Partially.
This appears to be referencing the famous Rat Park addiction experiments. Prior to this study, the scientific evidence matched pretty much what is still commonly believed, that certain drugs are addicting and anyone can become addicted and will have a hard time stopping because of chemical/biological dependencies. Rat Park tried to disprove this, by showing that rats, completely addicted to morphine, will not self administer the drug when subject to good living conditions (in striking contrast to previous studies that ignored the quality of life of the rodents).
Alexander's hypothesis was that drugs do not cause addiction, and that the apparent addiction to opiate drugs commonly observed in laboratory rats exposed to it is attributable to their living conditions, and not to any addictive property of the drug itself. He told the Canadian Senate in 2001 that prior experiments in which laboratory rats were kept isolated in cramped metal cages, tethered to a self-injection apparatus, show only that "severely distressed animals, like severely distressed people, will relieve their distress pharmacologically if they can." - Wikipedia
But, the scientific community has largely been unable to replicate this study. Living conditions are a factor, but they do not control addiction 100%.
Some further studies failed to reproduce the original experiment's results - Wikipedia
Recent research has shown that an enriched environment may decrease morphine addiction in mice. - Wikipedia
Summery: The channel is overblowing the results of a single experiment, and making the claim that (for humans) socialization is everything for quality of life. What is clear is that Rat Park did demonstrate that the current animal models for addition were fundamentally flawed and one dimensional. It did change the way we look at addiction fundamentally. But it failed to completely change everything we know about addiction, when it was found to be only partially reproducible.
As for soldiers breaking their addictions overnight, there is this study on this event. While only the abstract appears freely available, it specifically mentions a near instant and full recovery rate for these addicted soldiers. But it does not go into detail on exactly how it was measured, which I have some misgiving about. It mentions urine samples while the marines were being shipped out, were all soldiers who were found to have heroine in their urine considered addicted? While the followup research mentions interviews, were they simply asked if they were still addicted?