You're referring to the studies that show people have less children due to car seat laws but this article also covers some of the other consequences: https://ifstudies.org/blog/this-item-in-your-back-seat-might...

>I wouldn't want a third kid just because I don't want to deal with carseats anymore.

By the time you had your third, would the oldest still even be in a carseat?

But even then, three car seats is doable even in small cars: https://www.jefftk.com/p/three-car-seats