I use my pixel xl every day for two years and now it has a 10 min battery life. It's no longer a working phone and just a extra screen that's permanently plugged in.
8 years would be the Nexus 6P. I booted mine up last year and aside from the faulty SoC it's still a perfectly usable phone. Those dual front facing speakers are still great. Battery life is poor, but then it was poor to begin with.
I think we've also plateaued in terms of features. A phone in 2030 will probably have a brighter screen and slightly better camera, but outside of synthetic benchmarks I doubt it's going to look or feel any different than the Pixel 8 will in day to day use.
Not even sure we will have phones by then, they probably will more or less be fully handheld computers. I mean they are pretty much already that, but you get some good storage and flexibility in operating systems, some sort of keyboard config, and I don't even think laptops will be very common. My point is, I don't think a phone from today will even be relevant in 2030.