@aaaaa is right. This is nostalgia. Soviet people were writing anonymous letters on each other – the biggest source of information for authorities to convict people who brought a bucket of potatoes to their children during famine. In the past people had 6-8 children in a family.
My great grandparents lived in a village. The next door neighbour wrote a letter to authorities about another neighbour living 2 houses away from my grandparents’ house for bringing a bag of animal feed for his livestock. He got 8 years of jail for a bag of animal feed. Nowadays, you will get a fine and registration with police in most countries of the world.
In former republics there was a saying – don’t trust a Russian. One day Russians will stub you in the back because of jealousy or other reaons. Of course, this is a stereotype and people are different. Such saying existed for a reason.