>> "We went once a week to the council pool on the other side of town and pretty much everyone, all 30 of us, had learned all that by the time we finished and left for high school aged 11."

I had the same experience. Even the people that had a fear of water/drowning could swim at a basic level without assistance. I think we got a 1 hour lesson per week for around 8 weeks a year for 2 or 3 years.