Loom the population decline will suck in the short term because there will.be too many people relying in too few workers. But to be fair the boomers put this situation on themselves. They deserve it. Them and their sexual revolution started all this shit. Probably half this forum wouldn't even be incels if we were born like 50 years ago.
Of course the total world population will still be going up for a while, as some countries (mostly in Africa) will continue to grow in population, but sooner or later that will plateau and then drop off as well. Some people think the world population will peak around 10-12 billion.
And besides, long term, population decline is a GOOD thing. Imagine it being like 50 years from now when all the boomers and gen x are dead. We can have a comfy less populated world with less crowds, shorter lines, less traffic, everything is less expensive, etc (in the ideal situation).