The worst thing with PHP was people and standards, everything was a mess, there was no right way to do stuff and larger projects had like 100 different implementations for the same thing. PHP was really challenging to work with as coming to a shared agreement for how one should implement stuff was a recipe for personal conflicts.
So after a few years, I just started to code web applications with Java. A completely different, but much more enjoyable environment and much more friendly people.
I guess PHP is much more fun today, it was really fun to code in PHP as it was really simple and you feel productive and powerful. But in the old days, bad defaults often caused issues in production. And some of the documentation/knowledge sharing was dangerous(tutorials lacked warnings and information about preventing SQL injections).