Agreed with everything you wrote, except you don’t mention that for the second lifetime of the device (2,5-3 years) you are using a smartphone with mid-range specs from 2021 while with a budget Chinese or other mid-ranger you’d buy a new one with recent specs from whatever’s there in 2,5-3 years (hint: look at current high-end). I agree the specs are less and less relevant nowadays, but we don’t know the trend in 2-3 years.
Some trends we do know. More RAM, more storage, are a given. 5G is going to become more common, too (both in use as well as availability; for details look at your country’s 3.5 GHz licensing and rollout plans of providers). However, I also notice more and more mid-range smartphones getting an OLED and 90 or 120 Hz. As someone who’s used to a 144 Hz monitor, uses a work smartphone with such features, and who recently bought an OLED TV for a family member… yes I do notice the difference. Its very nice for scrolling and gaming, and also for those who prefer dark mode (hi!).