There are 8 pitchers in MLB with 15 or more wins right now. POR is the only one with an ERA over 4. The pitcher who has the 2nd best overall stats in MLB is 8-8.
When it comes to POR, you can either look at his won/lost record or his ERA. I've always believed that ERA is a more accurate stat for measuring a pitcher's season performance. Again, I refer to DeGrom.
That umpires answer to no one is explained by the fact that Angel Hernandez is still employed. He's umping at 3rd tonight, but he's been terrible for years.