As someone who develops in PHP, and continues to be generally annoyed by the way many HN commenters will dismiss the language out of hand, I really hate to be the one saying this. However, while PHP has come a long way and modernised significantly in terms of development practise, WordPress is really not an example of that modernisation. It may have applications for a basic blog, but I find it very difficult to take…
https://wordpress.org/showcase/archives/
I'm not sure this link is very relevant unless you're trying to posit that popularity ~= quality in some way?
If you're interested in further testament to its popularity, builtwith.com is always a fun read. I believe about 20% of the internet runs WordPress, a number which grows to approach 70% if you exclude sites not using off-the-shelf cms software.