The problem you see with these applications is that they are bad PHP, not that they are PHP.
If you would, go take a peek at the Symfony2 framework. It's positively brilliant code, and it's PHP--Fabian Potencier and friends are excellent programmers, and they write excellent code in PHP.
I'm currently in the process of building a migration path from our two different older PHP frameworks (MidCOM and Midgard MVC) to Symfony2, and I've really been impressed by the community.
They seem to be very receptive to new ideas, and passionate about code review. I've received lots of GitHub comments on my bundles even though the commenters probably would never actually use them.
And when I found an issue in Symfony2 itself that made integration with AppServer-in-PHP harder, Fabien fixed it within the hour of getting reported.
If you would, go take a peek at the Symfony2 framework. It's positively brilliant code, and it's PHP--Fabian Potencier and friends are excellent programmers, and they write excellent code in PHP.