In smaller companies, my experience is that you'd be at a distinct disadvantage compared to most full-stack developers. At larger orgs, however, there's plenty of room for specialization - depending on the size, "backend developer" may even be far too broad of a term.

That said, while the front-end can seem scary, it's alright once you dive in. With 2 years of experience as a Python developer, I wouldn't expect you to have too much trouble picking up Javascript and HTML/CSS.