I have found many people in our society treat most risks as black/white, and treat minor risk-taking as a taboo irrespective of potential benefits, while at the same time entirely ignoring serious risks that would be inconvenient to avoid. This goes double for anything related to children.
For example, localized air pollution from an idling pickup truck is obviously worse than standing outside near someone smoking, but I see people waving their arms around and making ridiculous faces and asking outdoor smokers to move, while I have never seen someone make an objection to the driver of an idling vehicle.
My 2-year-old kid and I walk around San Francisco barefoot, and on a daily basis strangers suggest that we are taking our lives into our own hands (because of the vanishingly tiny chance he might find a junkie’s discarded hypodermic needle, step on it in a way that injected the junkie’s blood, and contract a fatal blood-borne disease), but I have never once heard someone suggest it was a bad idea to walk in the vicinity of automobile traffic, objectively many orders of magnitude riskier. The society is almost entirely unwilling to slow automobile traffic, but the public library won’t allow us inside without shoes because a book might fall on our feet or something. Most people seem entirely unaware of the effects of habitually wearing stiff shoes on foot development and gross motor skills.
It is considered horrible for children to have a small sip of alcohol (for fear of profound brain damage? a slippery slope to moral decadence?) but large amounts of sugar are just fine and strangers are constantly offering children candy and juice and cookies etc., and once someone turns 21 years old then any amount of alcohol consumption is considered more or less fine as long as the person isn’t driving.
Brushing and flossing teeth multiple times per day is considered a mandatory part of basic hygiene, but again, nobody has any problem with people constantly eating sugar and simple starches, the main drivers of cavities.
Pregnant women are told to avoid all sorts of foods and activities (and sometimes judged severely if they disregard the advice) despite in many cases very poor evidence supporting those proscriptions.
Some people with medium skin-tone religiously apply sunscreen when they plan to spend a short while in the sun, but seldom consider the harms of insufficient sun exposure, or the potential risk of whatever gunk is in the sunscreen.
All manner of toys are marked “age 3+” including things that couldn’t possibly be choked on, and some parents seem to believe those warnings, but any family religiously following such advice is delaying their kids’ fine motor skills by 1.5 years.
Relevant to this discussion: many school-aged children end up chronically sleep deprived because school schedules don’t align with their natural sleep rhythm; the problems this causes (aggression/irritability, tiredness, distraction, problems with working memory, ...) are treated as the children’s intentional personal failings which they are then punished for.
As for co-sleeping: the benefits to our family have been very obvious. We all get more or less enough sleep, babies can eat whenever they like, and everyone maintains a close physical relationship.