In comparison to more powerful opioids like he mentioned, yes, it is less addictive.
But is the comparison even relevant? I mean he literally is comparing it to heroin(diamorphine) and fentanyl.
It seems like he is saying opiods are knives, and while most knives are sharp and dangerous, codeine is a butter knife and therefore not sharp or dangerous.
I'm sure there are plenty of studies out there who will tell you how addictive it is, although may require a higher dosage, but the whole "lean" aka liquid codeine w/ or w/o promethazine craze proves this stuff is addictive. Just google search "rapper quitting lean addiction". if that doesn't prove that codeine is addicting and the fact that people will actually pay far more for a weaker opioid than a stronger one says a lot. The whole lean craze is largely because a lot of people don't think it's addicting so it's socially acceptable, yet are paying absurd amounts of money for a weaker opiate buzz. Unless this person has endless money or quits, he will reach a point where he ends up supplementing his lean(codeine) habit with stronger opioids, until he realizes he's been chasing the same dragon all along. And unless this person stops somewhere along this way, the usual end game is heroin often laced with fentanyl because it's the cheapest.
The upside to a weaker opioid is that it will take longer or larger doses to build a tolerance, and so long it's not heavily abused then the withdrawals will be mild by comparison as well.
But to answer your question: it's largely dependent upon the person. I think it's something less than 10% of people that drink alcohol end up having addiction issues- but that all varies greatly by demography, genes, social support system, mental state, and so on. Some people can use hydrocodone and oxycodone with moderation for decades, some people almost immediately spiral into selling everything for heroin.
