Original link: PHP is the Best Choice for Long‑Term Business / Tomas Votruba.
This is obviously an argument from someone living of doing PHP, so it is not an unbiased opinion.
But I think he has a valid point. PHP is evolving slow but steady and try to keep backwards compatibility unless necessary (sometimes security concerns require a breaking change). The JavaScript framewok in fashion changes every 3-5 years, so constant rework.