I’m sorry that your phone is broken, but when you bought it Apple told you that it would warrant hardware defects for one year, and when you bought it, you had the option to purchase AppleCare+ at the time to extend the warranty another year. It doesn’t matter what the phone costs when you bought it - it was your choice to buy it. You could have paid less for an 8 or 8+. Apple isn’t required to provide 20% longer warranty coverage because you paid 20% more than you could have.
It sucks when these things happen, but they do, and you actually don’t know that it is a hardware defect. Did you ever carry it in a pocket and sit down and put stress on the phone? Maybe that broke the display. Did you ever drop it, even once? Maybe that broke the display.
Again, sorry it happened, but these things happen, and sometimes you have to pay out of pocket to fix them. Maybe think about AppleCare next time. Or buy a Samsung or LG or Pixel of you think you’ll get better coverage from somebody else.