Well I do use Haskell and Lisp regularly but for low level stuff they might not be ideal if you know what I mean. I would say memory safety is important to avoid buffer overflows, use after free, etc. which is extremely common in C programs even to this day. Of course you can say it's a skill issue. I do like C but it's kinda easy to make those mistakes so I'd rather avoid them when possible. Of course there can be bugs that cause security issue in the logic of the code as well but those are easier to test.