My customers and users of my applications don't care what it's written in.
But, you should definitely learn more languages as a programmer.
> And to anyone considering programming as a career, or trying to get into it... stay away from PHP.
This is the part I disagree with the most. The language is getting better and better with every release. It's incredibly fast, much safer to use (the Error exception type, scalar static type hints, all the garbage from the early 2000's has been removed), and easy to work with. The ecosystem (with the introduction of Composer) has _completely_ changed and reinvigorated the language. It's easily one of the best package managers out there. I definitely recommend giving PHP a look or a second change if you've written it off.