The only thing I can think of is that it wasn't typed correctly. That, or you could try typing it into the neighbourhood view and see if that makes a difference.
I'll type the code here, so that you can copy and paste it into your game to see if that also makes a difference, because before I added it to my userStartup.cheat, I occasionally mistyped it.
boolProp testingcheatsenabled true
Also, make sure you're actually holding SHIFT down when trying click, because sometimes I place my finger on CTRL and get confused when nothing works
If that doesn't help, then I'm stumped. There was someone over a decade ago that had a similar issue
here. Not sure if what was suggested helped, though.
When a game is predictable, it's boring.
That goes for any medium that isn't life.
That's why The Sims 2 is my favourite sims game.
It has elements of unpredictability and everything feels more involved.
The Sims 4 is another story altogether...