But companies might want to use PHP, because it has a rich ecosystem, which handles corner cases.
Chances are, if you want to send out bulk email, or connect to a payment provider, there's going to be a library in PHP that allows you to do that, often with long term support from an agency.
A corner-case I recently had was needing to decode an email. There's a function for that: quoted_printable_decode. This is a common situation for PHP. If you have some sort of issue around the web, there's likely to be a PHP solution.
And if you're a small business that needs a bit of bespoke software written, then you can easily hire someone, and know a decade later, you'll be able to hire someone if the requirements change.
Much of this can also be said of the Java ecosystem.
Just recently, I was using a small business that managed their bespoke business process built on a PHP CMS. They don't need 2000 reqs/second.