What are the population problems caused by negative population growth in some developed countries in western Europe?

The fertility rate in western European countries is declining year by year, which leads to negative population growth all the year round, resulting in a series of problems:

1) the labor force is insufficient, and some jobs can't recruit people, so we have to introduce foreign immigrants from Asia and Africa.

2) Consumption is sluggish and economic growth is sluggish. Young people are the main force of consumption, and the national economy is mainly driven by them.

3) The aging level is constantly improving, which leads to the increase of social pension expenditure year by year and the increase of young people's tax burden.

4) Countries with negative population growth seem to lack vitality and vitality, which makes people feel dying.