I am currently a full-stack developer at Penn State. I primarily use Drupal and as a result PHP for most of my projects, but I like to experiment and learn new technologies and languages.
Bootstrap does not require a lot of "learning" persay. Basically it writes the css for you and you just apply the appropriate classes to the elements you want the bootstrap style/js to be applied to.
If you want those jobs you should play around with it so you understand how to include it in your projects and get a feel for which classes and objects would serve as solutions for certain feature requests or design problems, but quick googling can easily get you where you need so I'd probably still apply as it doesn't change anything about the fundamentals it just does stuff for you.
Bootstrap does not require a lot of "learning" persay. Basically it writes the css for you and you just apply the appropriate classes to the elements you want the bootstrap style/js to be applied to.
If you want those jobs you should play around with it so you understand how to include it in your projects and get a feel for which classes and objects would serve as solutions for certain feature requests or design problems, but quick googling can easily get you where you need so I'd probably still apply as it doesn't change anything about the fundamentals it just does stuff for you.
I agree, "learn" enough to able to hit the ground running with it and you should be fine.