The recent bug in the Linux kernel Rust code, based on my understanding, was in unsafe code, and related to interop with C. So I wouldn't really classify it as a Rust bug. In fact, under normal circumstances (no interop), people rarely use unsafe in Rust, and the use is very isolated.
I think the idea of developers developing a "bugs antenna" is good in theory, though in practice the kernel, Redis, and many other projects suffer from these classes of bugs consistently. Additionally, that's why people use linters and code formatters even though developers can develop a sensitivity to coding conventions (in fact, these tools used to be unpopular in C-land). Trusting humans develop sensibility is just not enough.
Specifically, about the concurrency: Redis is (mostly) single-threaded, and I guess that's at least in part because of the difficulty of building safe, fast and highly-concurrent C applications (please correct me if I'm wrong).
Can people write safer C (e.g. by using sds.c and the likes)? For sure! Though we've been writing C for 50+ years at this point, at some point "people can just do X" is no longer a valid argument. As while we could, in fact we don't.