This is pretty contentious territory 
The short answer is: if you learn PHP you can get a job and that won’t change any time soon. That is basically true for any language, so don’t worry too much about reading the future and learning the best one. Just get good at one and then picking up others will be easier. Btw, every language is the best at something. For example, PHP is the best language for stirring up rage on this forum…
Rather than rehash everything, here are some previous discussions about PHP on the forum: