Pure speculation for obvious reasons, but as it’s pretty certain the new 6.1” iPhone 9 (or whatever it’s called) will have a single lens camera system, so you think it will be better then the 8 Plus dual lens system?
The 6.1" iPhone will definitely have a worse camera. The 6.1" will be a step back from the 8 Plus in some areas, it is intended to be a lower cost device.