Phone use definitely should NOT be adjusted for age. It should be if the player wants it or not.
Granted that I'm brand new to the Sims franchise today as an actual offline human being in her mid-40s, but as far as I understood it, this game was meant so that you could create your own reality the way you wanted it to be. So sure, I would play a woman in her twenties- why on Earth would I pay to play what I already am- a middle aged woman? I do that for free! That's stupid. So as a Sim in my early twenties, I was a single mother of a toddler and an astronautical tech who is introverted and reads and writes a lot. Certainly NOT someone who- regardless of her young age- has the desire or time to be on the phone 24/7 (even as an actual human being back in my twenties, I never wanted nor had time for that kind of ish!).
What upsets me about this the most is that when I have commanded my Sim multiple times to freaking take care of her toddler, she won't get off the phone I never wanted her to be on in the first place. What took the cake for me was when my sweet baby escaped the house and there was no command I could invoke that would make my adult Sim get off her freaking phone to go take care of her baby.
The phone use is ridiculous. I would never want it to begin with, but if there HAS to be an idle task, you should be able to select it yourself, such as "reading the book I packed in my bag" or whatever other idle action that matches the Sim's personality. For instance "reading the book in my bag" would match much more with my Sim's personality and my own desired reality than playing on the phone. That would also match the goals that the Sims 4 game has already set for my character based on her personality traits.
