After finding a mod to remove the ageing bug, I gave the new patch a try after all, and lord of the underworld, the fears are so annoying! I'm surprised at people reporting that they haven't encountered any yet, because I find them to be overly intrusive, even more so than lifestyles. After playing with a five-person household for two or three in-game days, every single one of them has developed a fear of not fulfilling their dreams. It says that talking about their fears to other sims might help, but that interaction is never available. Half of them also get a fear of a dead end job every time they go to work, and are perpetually tense, sad and/or angry as a result.
Good thing you can turn them off, which I did. Such a shame, because this feature sounded so promising.