"No one is really looking for a PHP developer right now. And all the front end jobs want React/Redux experience or Angular."
So, not learning React doesn't seem like a good call unless he wants to stay in the backend. No matter what he will be learning now, he will not have "real world experience" with it. All he can do between jobs is learn. What's your advice exactly? What does "looking at how Python has progressed" even mean?
Take an existing project you wrote in python and modernize it for newer style, maybe it was in legacy 2.X for compatibility with something and needs to be updated. Maybe convert to a python framework that is popular now (there's not so much churn in python so a past framework might just be updated.)
Taking a past project and modernizing it allows you to mix discussion of real world experience with your understanding of new things. Where things are just updates you blur perception and significance of the age of your real world experiences.
But switching completely to patterns, code and development processes you have never used before even by analogy is taking that to the most tenuous extreme..
Who knows maybe the OP's past JS experience was in SPAs in a functional style using node tools and an IDE and react is almost reasonable.. But that seems unlikely if python and php were the first languages the OP thinks of.
It makes more sense to milk and refresh past connections to Python to find a new subfield than to try to stay in web development by switching to JS (if it was your 3rd language from 3 years ago) to move from Backend to frontend in the months right before almost every language will get an opportunity on the frontend..