"Mediocre" by what standard I ask. Wealth? Maybe. Happiness/Life Satisfaction? Not all roses, but hardly.
In fact, because it's on topic, here's the full lyrics: https://www.streetdirectory.com/lyricadvisor/song/ucoowl/wha...
People are seeing that that version of "success" isn't worth your whole life. They're deciding to not chase it. That may not fit with the WSJ's version of the world, but from where I sit, it looks more like wisdom.