I think one reason is that the community is doing too good of a job. The language is pretty sane, it solves most problems right, the libs and docs are good, and the general direction thinks take is reasonable. And it's free not only as beer and freedom, but also free from business influences. The PSF is really giving away pretty much everything.
Everybody contribues a little (we have the brett canon team from ms, the guido team from dropbox, the alexi martelli team from google, mozilla even donated for pypy, etc). But it's nothing massive. Nobody said "ok here is 10 millions euros, solve the packaging problem".
Compare to JS: the language started as slow, with terrible design, and no consensus on the direction to take. So eventually, people (Google first) pourred a load of money to it until it became usable, and they had a cleaner leadership. They had huge problem to solve on the ever expending market that is the web plateform. Of course JS as the unfair advantage of a captive audience and total monopoly on its field.
Remember Unladen shallow ? "Google" attempt to JIT Python ? It was just one guy during his internship (http://qinsb.blogspot.fr/2011/03/unladen-swallow-retrospecti...).
And look at the budget the PSF had in 2011 to help the community: http://pyfound.blogspot.fr/2012/01/psf-grants-over-37000-to-... I mean, even today they have to go though so many shenanigans for barely 20k (https://www.python.org/psf/donations/2018-q2-drive/).
But at the same time you hear people complaining they yet can't migrate to Python 3 because they have millions of lines of Python. You hear of them when they want to extend the support for free, but never to support the community.
It's ridiculous.
Also compare to PHP: the creators made a business out of it, plain and simple.
Compare to Java/C#/Go: it's owned by huge players that have a lot of money engaged.
Python really needs a sugar daddy so that we can tackle the few items remaining on the list:
- integrated steps to make an exe/rpm/deb/.app
- JIT that works everywhere
- mobile dev
- multi-core with fast and safe memory sharing
There are projects for that (nuikta, pyjion, kivi, etc), but they all lack of human power, money and hence integration, perfs, features, etc.
You need a simple way to code some GUI, make it work on mobile or desktop, turn it into and exe and distribute it.
You need a simple way to say "this is a long running process, JIT the hell out of it".