Interesting, can you elaborate? What part of the city or surrounds do you find this to be true? I've found the reliability and mix of routes via tunnelbana, pendeltåg, trams, buses, and boats to be really good and know many Stockholmers without cars. Of course, road trips and moving large items become more of a hassle without a car, but can often be worked around with rentals/delivery srevices. Further, the more remote you get, the density of public transport options do become sparse, if an option at all. But within the radius of the tunnelbana, living without a car is very achievable. [edit: saw your other comment about further out areas, late night journeys and MTR, which are fair points. Cars are super convenient in many ways, no argument there.]

I've lived in central Stockholm for 10 years with kids, it's amazing, but perhaps not for everyone. I also lived the car dependent life in the US and it made me mildly depressed.