Socialization past early childhood
The more borders open, communities mix and everybody travels, the bigger is a need for social training for older people. When my husband and I first came to the US as graduate students, our "English for Teaching Assistants" course included what I consider "social training." For example, we practiced standing at about a yard from the person we talk with - not more like in Western Europe, not less like in South America. Or, we practiced answering questions within 2-3 seconds, not up to one minute, as in China or Eastern Europe.
Also, autistic people may need more explicit learning in this area.
Most people who enter social media need socialization help learning netiquette. For example, in the last couple of years, many 50+ people joined FaceBook, and many 25- people started to leave it as the social climate there changed so much.
People who enter a new profession, which more and more people need to do repeatedly during their life, also have to learn, or create if the profession is new, different social norms.
Changing social norms consciously is another big part of social learning. It's something we have to teach kids more than we do now. Community forming, social norm design and establishment, changing existing social norms, and recognizing the non-malleable ones.
Good points, all
