I think the change to force your cities to be connected is a good one overall. It made no sense in civ 6 how you could just buy your land out, build a campus on the other side of a mountain range, and it would magically be connected to your main city.
Is it frustrating? Yeah. One of my games I built a city that I thought would be great, there was a mountain range that snaked around, and I had a tile with 4 mountains around it. Perfect, right? Yes, except that bordering the mountain range was a string of resources, and I basically couldn't wrap my urban districts around those resources to snake them around to be able to get any urban districts on the other side. But it's something to get used to - next game, if I see the same setup, I probably need to move my settlement up, so that I can plan on getting my districts around the bend and able to fill in the gaps. Or in the above case, if you really want it out by the ocean, you have to plan your districts out in that direction.