They are proposing this solely with funding pensions in mind. And even worse, it’s a central bank dictating socio-economic policy.
The bank isn’t dictating policy. The bank is telling people what the numbers mean.
A 67-year-old German has a life expectancy of about 84. So his pension will have to support him for 17 years. There is just not enough money in the pot.
However, if he works until 70, there is more money in the pot, and his pension only has to support him for 14 years. This is an easier problem to solve.
Of course, people should just make their own intelligent decisions about these things. But that ship sailed a long time ago.