As others have mentioned, WordPress is still huge. I believe Facebook is still mostly php, and I'm sure there are tons of sites started 2005-2010 that are still

As others have mentioned, WordPress is still huge. I believe Facebook is still mostly php, and I'm sure there are tons of sites started 2005-2010 that are still php. PHP is easy to deploy, atleast from the start, but was difficult to use compared to python and ruby. It's deployment model also encouraged people to edit directly on the server, which lead to all kinds of problems. So it got a bad reputation. I have heard that it has fixed many of it's inconsistencies, but many have already moved on. The ones still using it are either stuck, or happily quiet.