I see the reasoning. Especially considering not all development takes place in California. And don't assume top adult companies don't pay well for developers doing PHP. It's hard finding good programmers regardless of the language.
PHP and Perl have a large foothold around the world, and being located in a nation other than the USA doesn't make a programmer less skilled.
So, with PHP, you have a higher chance of finding good programmers, though you'll have to sift through a lot more people who claim to know PHP. You'll be able to look in a lot more areas, and those areas can offer cheaper rates. And finding a Ruby programmer with ample experience is going to be difficult. I don't know many Ruby programmers who've been programming in the language for at least 5 years.
This is especially true where cost of living is lower. Put all of this together, and using Rails or Django makes little sense.
The article is a bit old, but should still make for an intersting discussion.