I think they'll be supporting older devices with iOS updates even longer going forward. The 32 vs 64-bit CPU was the line in the sand this year. And the iPhone SE has the same CPU as the 6 but is still considered a current model.
> the iPhone SE has the same CPU as the 6
The SE uses Apple A9 CPU from the 6S.
I think prices have stayed pretty much the same or become lower over the years. You can get a 64GB iPhone 8 this year for $699, vs $749 for the iPhone 6 in 2014. I think the iPhone 8 is still a pretty "premium" experience, even if Apple now has a more fancy and more expensive model.