Can I ask why? In my limited experience AI forward settling doesn't stop any styles of play. Maybe it's just annoying which is enough.
I'm revisiting Civ a lot the past few days and I realise Forward Settling is the reason I often quit playing in the first age. Just now, I had a game playing as Egypt (coastal city in the top of an upside-down U shaped landmass, so imagine two landmasses leading south from the central one).
Silla to the west, Mississippian to the south east, Maurya North east. Then interspersed city states, west, north west, east, and further still. Then north of Mississipian are Maya and Rome. To the west of Silla is open land, to the east of Mississippian is open land, to the north of Maurya is open land, to the North of Rome is open land, to the east o Maya is open land. In short, I'm boxed in.
I'm not able to settle any cities, without traversing their kingdoms and settling a colony on the other side. I could incorporate City States, but they are, frankly, not that aptly placed. Yes, I could go to war with some, but I don't want to.
So yes, it doesn't stop a style of play: peaceful. In fact, almost any play except moving to war or three settlement challenge is out of the question here.
My strongest wish right now is a loyalty mechanic like in Civ VI.