It's a dying breed in that it's being outgrown by others and the niches where it's the best choice are getting fewer, but it's not going away soon either.

For example high performance multithreaded code is now largely written in languages that are better for concurrency correctness, because the added development speed translates to added runtime performance by letting you iterate more in the same timeframe/budget.

A good understanding of the how the C/C++ memory safety bugs happen and lead to vulnerabilities is important to learn if getting into it.