I think the big difference in 6 is that you aren't penalized for building wide vs tall, in fact you're encouraged to do so. You need as many useful district bon

I think the big difference in 6 is that you aren't penalized for building wide vs tall, in fact you're encouraged to do so. You need as many useful district bonuses as you can get, which are often improved via the Pantheon. Since any City can only have one of a specific district, you want to build many cities. Civ 5 encouraged building Tall. So it was far less likely to end the game with 15 cities unless you played one of the few leaders that needed Wide expansion. In 6, there is really never a logical stopping point for building a new city. You either stop because you don't have space, you're busy with war, or it is so late in the game and you're just trying to end it. Otherwise, it's worth settling in a bad spot just to control more of the map or get a district bonus. But, yes, I don't think this is new to the series overall.