I am not surprised that mods break and get abandon. Somethings things happen that prevents some modders to go back and a few unfortunately have passed away. Sometimes people try to pick up mods; but coding is really hard to do if you are new and trying to do something that changes the game. Even people who been doing this for awhile can struggle for awhile as they have to find the root of the problem which takes time, find a way to fix it, etc....it is also really time consuming and it isn't their job or main source of income, so that is also why it takes time for some to get updated, if at all. It is just a hobby for many.
Though Sims 4 Studios do have a lot of good resources and tutorials as their focus is modding. There is even resources for making script mods (I hadn't been successful with it yet; but at least the opportunity to learn is available).
The longer a well known game is out, the more some mods will be abandon and some new ones appear.
