>>> Of course there is. You could, for example, survey developers
So objective measure is which language is preferred by more people? I'm not sure how it is an objective measure but I'm pretty sure PHP would win on that.
>>> If you wanted to be more scientific, you could
Nobody even did that. I still encounter a lot of people speaking as if they personally did.
>>> don't actually have that much experience working with a language like python or ruby
That's meaningless argument because it can not be disproven by any possible means - for each counterexample I provide of people that know a lot of languages and still think PHP is ok you'd say "well, and I know hundred PHP developers who don't know any other language". Maybe you do, maybe you don't - how anybody could consider that an objective measure of anything or a measure of anything except the characteristic of people you are surrounding yourself with?
>>> It's rare to find people with lots of experience in both php and ruby/python who prefer php.
What is rare? I know a number of people who could work very well in any common language, but that means nothing - I could also write "I know hundreds of people that know all languages in the world and prefer PHP". Your personal acquaintances don't like PHP, so what? My personal acquaintances don't speak Mandarin. Does it mean nobody speaks Mandarin or Mandarin is a failed language? It just says something about me, not about Mandarin.