"It's easy to start with" is only a virtue if that doesn't come with "it turns into a tire fire a year later".
I have worked with people who make same claims as you resulting in us spending endless hours doing preparing for a scale that never happened.
Guess what our client felt about that invoice?
It's a pseudo problem, a theoretical problem, something that can be solved even though it might not be as elegant as the purists would like it to be. But it can be solved if it has to. Most often it doesn't.
That isn't a "pseudo problem".
Popularity is a bad, bad metric of a tool's quality.
Yours or mine definition of quality is of no importance to this discussion.
Some people just scratch the itches they have, right now, not the itches their expertise makes them think they should have, or the likes of Google or Facebook make them think they might have in the future.
And that is fine. Nobody is telling anyone to use PHP for their huge project, right? So why tell people they shouldn't use PHP for their mortal ones? Because at some point, down the road... can't we cross that bridge when we come to it?
No, and that's the problem. Nothing gets rewritten, it gets hacked on. PHP makes hacking on things, past a really low bar, really hard given what you get out of it. And the early benefit washes out pretty quick once you spend more than a couple days on a project. Setting up Play 2 (or Rails, or Django) is going to take me maybe five minutes longer than rolling up a project skeleton with Composer and I immediately start reaping the benefits of a sane environment. It's probably going to take me less time to be functional with any of the above than Symfony2, and I'm not inexperienced with it.
You pick your poison on day one. PHP's poison is bad for probably the 50% case, really bad for the 25% case, okay to good for the 10-25% case.
(Wordpress is not part of the last one. Neither is Drupal. I don't run either on any system I need to be able to trust. Even with FPM it's too much of a pain in the ass for the benefit I get from it.)
In those last 10% you are right 50% might be really bad, 25% ok and 10 good.
"7 Reasons I Switched Back to PHP":
I threw away 2 years of Rails code, and opened a new empty Subversion respository.
Then in a mere TWO MONTHS, by myself, not even telling anyone I was doing this, using nothing but vi, and no frameworks, I rewrote CD Baby from scratch in PHP. Done! Launched! And it works amazingly well.
Mind you, this is from 2007 and there's more to the story -- Sivers learned a lot, as he says, from hiring a Rails guy and from the attempt to use Rails:
It’s the most beautiful PHP I’ve ever written, all wonderfully MVC and DRY, and and I owe it all to Rails.
At the end, he describes his 7 reasons why PHP worked out better in his case and they may well make sense in other cases as well -- that is, while some of these reasons reflect his personal tastes (e.g. #6 - I LOVE SQL), some are solid business reasons, like reason #2, which I'll quote in its entirety, since it's worth keeping such considerations in mind:
#2 - OUR ENTIRE COMPANY’S STUFF WAS IN PHP: DON’T UNDERESTIMATE INTEGRATION By the old plan (ditching all PHP and doing it all in Rails), there was going to be this One Big Day, where our entire Intranet, Storefront, Members’ Login Area, and dozens of cron shell scripts were ALL going to have to change. 85 employees re-trained. All customers and clients calling up furious that One Big Day, with questions about the new system.
Instead, I was able to slowly gut the ugly PHP and replace it with beautiful PHP. Launch in stages. No big re-training.
I'll suggest that, like other writings by Sivers, this is worth reading since the issues he dealt with in migrating to a rewritten system are ones that are not uncommon.
(For a list of all his blog posts about entrepreneurship, music (and the business of music), life, etc.:
This was also a rewrite. He already shot himself in the foot with PHP the first time around, then chose this brand new thing called Rails as his basis of a new codebase about as early as humanly possible without your initials being 'DHH', then went back to PHP for several reasons, some of which are still hotly debated today (SQL vs ORMs, frameworks vs. custom code or minimal frameworks, etc).
It's disingenuous to draw any conclusions about Ruby or Rails today from its state 7 years ago (likewise for PHP).