Given that as far as I know, room-sharing is not standard Western parenting practice, I believe they have backed up with an appeal to authority the idea that Western style parenting is harmful. Furthermore, link [1] contains a link to [3] which is an recommendation from a pediatric journal that provides links to scientific papers that suggest room-sharing reduces SIDS risk by up to 50%. (see bullet point 4 of link [3]) Thus I think the appeals to authority are backed by evidence.
Thus I think that the article could have made a stronger point if they had talked about room sharing more instead of bed sharing, but I think they do have an evidence backed point that Western parenting is potentially harmful. They avoid ruffling parent's feathers too much by understating their point.
[1]: https://www.aap.org/en-us/advocacy-and-policy/aap-health-ini... [2]: https://www.lullabytrust.org.uk/safer-sleep-advice/ [3]: https://pediatrics.aappublications.org/content/138/5/e201629...