Tl;dr human birth rates are falling universally and globally and at some point in this century will mean a decrease of the world's population. The effects of this will/has been felt in stuff like pensions/retirement and so far, noone has proposed any solutions other than increased immigration and denying women abortions. So what should we do to solve this? Should we even find solutions given that stuff like pollution and climate change is man-made?

From the environmental standpoint shrinking of human population is often quoted to have desirable effects, and that's reasonable. But from the point of view of our daily lives and functioning of the human society, what negatives could we then expect? (I mean a soft decline due to lower birth rates, not some abrupt events.)

For example, with smaller population fewer music albums could be made every year than some time before, and people would maybe feel less inspired and satisfied. Less scientific research, less choices for relationships... and maybe other things? Would being more technically advanced compensate for the issues? Won't we feel ourselves in oblivion and romanticize the "numerous" past?