Using a phone that long is risky due to the lack of security updates, especially if you're using it for work. People not using phones longer is a problem, but the bigger issue is manufacturers killing support so quickly to force people into upgrading.

I recently upgraded after 5 years on an iPhone because it reached the end of its support cycle. I considered another iPhone because 5 years of support is great, but really didn't feel like paying another $1000+ for what is essentially the same phone I was already using, just with a different body. So I went with a used Pixel 7 on ebay and installed GrapheneOS on it, and I'm very happy with it. I'm getting the same 5 years of support, a more secure OS, and I'm recycling at the same time!