It's a lie justification/propoganda.
They show a graph showing that populations are heavier older than young, that people aren't reproducing enough.
They don't tell you that keeping an old person alive is fucking cheap and easy, and has been managed for thousands of years.
They don't explain what will happen when the new population ages and needs more people to sustain it, and that this is literally the definition of a ponzi scheme: that the old are constantly paid by the new money coming in - but eventually new money runs out/population hits a critical mass where you're living in Indian/Chinese people per square metre.