Well firstly the gotchas very rarely get me. I found the same with Javascript. The inconsistent and odd data conversions make fun slides to denigrate the language, but in practise they seem to be easily avoided.
I realize posting a 40 minute video to support my point is a bit lazy and unfair but you seem aware of some of the key points fortunately.
First let me admit that we have a php legacy codebase, so porting that to another language, even if we had a strong desire too would probably be prohibitive.
I definitely feel super productive in PHP. I've been able to knock out a new app feature in 1 day, which to build the equivalent in Java would have been at least 5. It's very easy to write code fast, and then come back and refactor it later. Using PHP Storm as an IDE with a very good debugger and PHPUnit to build a suite of tests for everything we do means that gotchas are always eliminated before production, and with PHP I find things are either working or completely broken with not much in-between.
I guess having a strong unit test suite, or really it's more of an acceptance test suite, is something you can do in most languages, but the assurance it gives us enables us to share large code bases between teams, doing frequent merges of features. You can have large numbers of programmers with varying abilities and even programming styles hitting the code without too much headache.
The talk also mentions state. Not sharing state between requests except explicitly. You don't have to worry about complicated background threads, resource leaks, memory leaks. Even crashes are less of a big deal since you just lose one request to it, not the whole server like with Java et al.
PHP's array is a swiss army knife with lot's of useful functions for transforming data, which is a lot of what we do on the server. I can map, reduce and filter data. I can dynamically handle arrays or single objects in the same function, or handle arrays of different kinds of data without any fuss. In short going from what I want to happen to having it happen is very fast.
Background tasks are queued and run on other systems including some written as bash scripts or in Python, Go and node.js. These languages are a better fit for these jobs and so we ditch PHP for those.
What Facebook is doing with HHVM (run faster) and Hack (add type safety as needed) is pretty interested and we've adopted the first but not yet the latter.
Hopefully that's flavour of what I like about using PHP. I have not written more than a few lines of Ruby so I cannot comment on that. I have done some maintenance work on a Python server but not with a modern framework. I'm not sure Python with a modern web framework offers all of the advantages I've mentioned above but I am open to being enlightened on that.