I agree with you that there should be no price increase, but I'm not that optimistic. There is a price premium to dual-stack OLED, and I think this may be how they will manage it, by simply dropping the 128 GB price tier.Wholeheartedly disagree.
256gb should be the new base model, without base model price increase.
Storage is inexpensive. It's just Apples marketing strategy to Push people upward the ridiculous pricing tiers.