Personal PoV: I think it is important to learn the C abstraction because lots of senior people in the industry talk in that abstraction level and if you're not able to communicate on that level, it may be a communication hurdle for you.
Lots of people certainly can survive without knowing any C, I'm just saying that it is not an irrelevant thing and if you have the time to invest in learning a bit more than the basics, it is not a waste of time.