I understand why people still have this perception, I imagine due to relics of the past of the PHP 5 (or earlier) era. But those days are long gone, and I believe PHP 8 has some a nice job of adding modern features and improving developer experience.
Wordpress is the obvious answer to your question, but its codebase is admittedly still stuck in the past in many ways. Nobody would write it that way if they were starting from scratch today.
There are plenty of “serious” companies using Laravel or Symfony. Take a look around those codebases if you want to get an idea of what solid modern PHP design patterns look like nowadays. Nothing “cheap or not very technical” about them :)
Wordpress is the obvious answer to your question, but its codebase is admittedly still stuck in the past in many ways. Nobody would write it that way if they were starting from scratch today.
There are plenty of “serious” companies using Laravel or Symfony. Take a look around those codebases if you want to get an idea of what solid modern PHP design patterns look like nowadays. Nothing “cheap or not very technical” about them :)