You're probably going to get a lot of responses with "this is why rails is bad" and "this is why django is good".
Though having worked extensively on both and not having a particular love for either, the simple answer is this (IMO):
Python skills transfer to other industry disciplines far better. Picking Django (vs Rails) is just a good career move. Data scientists use Python heavily (scipy, numpy). Many universities teach Python as the first scripting language. Python has a much stronger foothold outside of web frameworks.
I switched from Python to Ruby because I wanted make my own hobby website and Ruby on Rails looked great. And 14 years later, my website has long gone, but I still use and love Ruby for all my scripting needs while my Python skills have faded.
And it's a real problem when I want to do hobby signal processing or deep learning stuff.
Python has won that segment of the market and I better get with the program.
Heck, I'm looking at this survey and wondering if I should put Python on my learning queue. It does seem to be in use across a lot of disciplines, including some of the most popular emerging techs.
and honestly. You'll be 60% competent within a week or two. There's a long tail of language features and idioms, but that basics get you so far in python.
I'd contrast this with say Java, my other mainstay and Scala which I'm picking up in pieces right now. Java is quite explicit and has quite a bit less built-in so you don't feel very capable or productive for quite a bit longer. Scala has so many syntactic variants and features that the volume of stuff I have to learn is relatively vast. Every third block of code I read uses a new unheard of language feature or concept. ... and I have some functional programming background.
Though having worked extensively on both and not having a particular love for either, the simple answer is this (IMO):
Python skills transfer to other industry disciplines far better. Picking Django (vs Rails) is just a good career move. Data scientists use Python heavily (scipy, numpy). Many universities teach Python as the first scripting language. Python has a much stronger foothold outside of web frameworks.