unless you have money to burn

All these flagship devices are aimed at people who do have money to burn. The ordinary models based on 5 year old tech are absolutely amazing at all the things people do with their devices. No one really needs any of the newer features.

This is the problem that any mature product industry faces - once the basic product is good enough for 99% of the users it becomes a boring commodity. Innovation stops selling devices because it only adds things most people don't want. The result is either cost driven price reduction as manufacturing processes get cheaper, or silly features (like fragile folding mechanisms) that the company can advertise to keep the perception of being high-edge expensive cutting-edge tech despite most buyers opting for a product that doesn't have any of that stuff but are still willing to pay for the status of having the brand.