It happens everywhere.

Current structures favour moving to cities. Farming and mining (which are the biggest job sectors that require people living in rural areas) are getting more and more automated, which means that there are fewer and fewer jobs in these fields. At the same time, huge, automated businesses win financially against smaller businesses operated with manual labour, so the small farmers are dieing off as well.

Manual jobs are often seasonal (e.g. picking fruit), and they are filled with seasonal foreign workers who don’t live in the rural areas either.

WIth fewer people living in rural areas other jobs (e.g. factories) also move to the cities, further removing rural jobs.

All of that push more people to move to cities and so on.

The impending demographic change accelerates that trend too.