I just went from a 6S+ to a 15 Pro, so I'm an example of this. However, there are some apps that just don't work on the older devices. Snapchat would not work on the 6S+ with the latest OS available. Eventually, the camera took enough tumbles that I'm assuming the lenses were no longer aligned as nothing was in focus.

Also, an iPhone provides so much more utilitarian purposes than anything Nokia ever released. Something as simple as those devices would be much less noticeable if replaced by mood.