But the biggest reason (for me) to replace phone is to get security updates; buying used is counter-productive to that end
Apple supports their phones for a very long time. They updated iOS 12 this year with security fixes, so that covers iPhone 6 and up.
https://www.macworld.com/article/675021/how-long-does-apple-...
I should have quit when they instituted their very obvious alt-right agenda pushing blocking bullshit, but whatever. Better late than never, and forcing third parties out was also a good boycott reason.
I did not realize how much time I spent in Apollo. Damn man.