Are you sure?
Apple still deliberately throttles old iphones and has had an issue on many older models. I don’t know what makes you think they’re made to last.
Iphone x has screen burn and colour shift due to the way OLED screens work.
Iphone 8 has logic board issues.
Iphone 7/+ has audio ic issues and no service issues.
Iphone 6/+ has touch ic issues.
Iphone 6s battery randomly dies.
There’s quite a bit of material on all the iphone issues online and a few ongoing class action lawsuits. You should check it out. I’ve never heard anyone ever claim the things last a long time before. That’s really not their spiel.