People today appear less willing to trust or help strangers than in the past, and some regard this as a positive development. I strongly disagree, since reduced trust damages both individuals and society.
Those who see some benefit have a point. The modern world contains genuine dangers, including online fraud, street crime and scams, and being cautious about strangers can protect people from harm. Parents who teach children not to talk to unknown adults, for example, are acting sensibly. A healthy degree of scepticism may also prevent people from being cheated by dishonest sellers or fraudulent charities.
Nevertheless, a general decline in trust has negative consequences. Societies function because people cooperate with those they do not know, whether by following traffic rules, paying for goods or helping someone in difficulty. When individuals no longer offer help, the vulnerable suffer: an elderly person who falls in the street may be ignored, and a lost tourist may receive no assistance. Lack of trust also makes life more expensive and stressful, as people spend money on security systems and legal contracts, and it weakens community ties, leading to isolation and loneliness. Research in many countries has found that communities with higher levels of trust tend to have lower crime, better health and stronger economies. In addition, constant suspicion often exaggerates the actual risk, because most strangers are harmless and willing to help.
A sensible approach is to be careful about specific dangers, for example never sharing bank details online, while remaining open and kind in everyday situations.
In conclusion, sensible caution is wise, but a general decline in trust and willingness to help weakens communities and increases isolation, so I do not consider it a positive development.