Core Demographic
@Jimmy - the core demographic is that group of people which will pay money for a new phone every year or so and will then subscribe to paid-for services. The older gits (like me) are happy to hang to an iPhone SE for years as long as it does phone, SMS, mail, music and a bit of internet to solve pub arguments. No one's making much money out of me for tech: I'm SIM only so don't get bothered for upgrades. I haven't bought a new smartphone for a couple of years, and that was a spare SE. I don't subscribe to Netflix, Spotify, etc. and if I buy music it's disc shaped.
Their core demographic wants something newer, thinner, <insert something that looks good on a big screen presentation>, every couple of years - or at least they are conned into thinking that they do either by peer pressure or marketing/advertising. The problem that the companies have is coming up with something that ticks all these boxes and will convince people to part with serious money. The annoying thing is that the foldable phones are quite chunky in their folded state and if they made a normal phone that thick they could put in a headphone socket and card slot and a huge and removable battery.