I'm finding the whole idea about cars for the sims4 interesting, because it feels like they often have to take this into account with the their world design to a point where it feels like they have to design their worlds and everything in the game around the fact that there are no cars that our sims can use.
Many neighborhoods in the world have very few or no parking spaces at all so neighborhoods often feel like public spaces (where you are not allowed to park cars) which I guess is fine if that's what you are going for with your house builds but if you want to have a neighborhood that doesn't feel like a public space then you are very limited. One neighborhood in Growing Together is designed like a typical suburban neighborhood with similar houses with garages except the one which you get to build on.
It's also interesting with Maxis HQ being based in California where they have a lot of cars everywhere and they have taken the decision to ban petrol fueled cars by 2035, so the game could have showed the interesting time we are living in now where the design of cars and how they are being powered is changing. You could argue that only focusing on bikes is better for the environment but if the game doesn't have any cars at all for our sims to own then you are not depicting those changes anyway.
Maxis likes to be trendy with their pack designs and this game have the opportunity to show the challenges a lot of people and families are facing with them wanting to be friendly to the environment, but they also don't want to spend huge amounts of money or try to adjust their lives to not using cars. If you live in a city you can often adjust but out in the country you can't just bike several miles to places or use non-existent local traffic. The challenges that a lot of people face in real life with being able to transport their children or elders to places are not shown at all either in the game, sims are just fading away and teleporting to places.
So I think it was a missed opportunity for them to not focus on cars early in the game because we could have seen a lot of interesting game design by now, instead they are just props or are just assumed to be used.
And no, I don't think the limitations of the game are a reason for us not seeing them either, I understand that we will not be able to use them to travel around the neighborhood but I don't see how they could not work like the rocket for example which have plenty of animations and shows the sims entering and leaving the lot.
So tldr, them not including cars makes other elements in the game feel less impactful and important in my opinion.
