I'm still using an iPhone 12, and given I have a proper camera, see no reason to (ever?) upgrade. After a battery replacement, it still runs perfectly well. That seems like a problem for Apple.
OTOH, maybe the iPhone Fold will turn out to not be two giant slabs of glass that still won't fit in your pocket. Maybe it'll be a reasonable size folded up, and big when unfolded. A person can dream...