Unclear if it just sims with the High Self-Esteem trait or all sims, but my sim who I aged up from a child to a young adult not only has constant (or near-constant) moodlets regarding the high self-esteem trait that happen way too frequently, but also concurrently has moodlets as if she is still growing or lowering her self-esteem, despite being an adult and already having the high self-esteem trait. As a result, my sim is constantly confident, no matter what is happening, and the game is boring and annoying.
This is something that has plagued me for a long time across multiple saves, and I used to just delete the trait & moodlets with UI cheats, but I stopped using mods a while ago and now it's making the game very frustrating.
I use a cake to age up all of my sims, not cheats. Fully up to date on PC.
No mods, clean save started within the last month or two.