https://memory-alpha.fandom.com/wiki/Wh ... _(episode)
It's about the ozone, and as anyone who grew up in that era knew, we are all about to die because of the ozone. Anyone who is used to modern media wouldn't even be able to recognize it because they've been boiling in it for so long.
Note that this is a 2007 review of the 1988 episode! It was considered heavy-handed even by 2007 standards. I couldn't find any contemporary reviews, but if anyone has some I'd like to read them.Michelle Erica Green in her review for TrekNation, described "When the Bough Breaks" as "tedious, plodding and didactic" with a "preposterous" ending. She thought that the plot element of ozone damage was not optimal and that the quality of the episode was typical of the first season.
I don't think it was particularly good and therefore worth watching for any reason other than to realize how ridiculous media is now and it's not you that's going insane. The idea that media has always been like this is something lifted straight from 1984 — we've always been at war with the ozone, and VTMB was full of fat gay nigger worship with ugly women.