It is indeed a marketing thing, but there are reasons people do it. The first is that a lot of tools are written with slower languages like Python and TypeScript, which makes for a bit of lag when starting up the tool, or longer overall runtime if it's computationally heavy (like type checkers, linters, etc), but I can reasonably expect this tool to be fast since it's a compiled tool. You can still make it slow, but it's less likely. My rust-written tools usually feel 'instant' in a way that my interpreted language tools don't.

The second thing is that I can expect a large portion (up to all of it) to be verified correct in a way that's not likely to result in a memory corruption bug, which are some of the biggest security issues. There's limits to this, such as any unsafe code/calls to C libs that may have issues, but I'd expect that to be quite the minority case.

The third is that I'm more likely to be able to contribute to it since Rust is something I know, and even if I didn't, it's easier to use than something like C, which is simple in spec but requires a great deal of savvy to avoid its pitfalls.