With video game consoles, you have a single device where micro-optimizations are constantly done, new features are added, and all software can be purpose-built to work really well on that specific hardware. All of that for ~7 years means a really fantastic user experience and a massive community of people that have collectively worked through solutions to common problems and forced the company's hand on defects (joycon drift, for example). It also means tons of high-quality hardware-specific accessories, both from the company that made the console and from third parties.
For about five years it seemed like every flagship spanning generations was the same SoC
Yes they are, by refusing to release security updates for older models.
I don't want to buy a new phone, but likely will have to due to support ending so they can sell more high margin hardware.
If you don’t like the terms, go with a Linux distro phone
Also Linux distro phones aren't practical ways to participate in society unfortunately.
No one is forcing you to buy anything you don’t want.
Also, the OS and apps need to take advantage of new hardware, so it’s not a surprise if your seven year old phone becomes slower.
If you don’t like the status quo then I would go with a non-iOS and non-android phone like pine phone, Mairena, librem, or anything else that based on a more open Linux distro.