I would say it’s the opposite. coreutils is core utils, you cannot write shell scripts without them, they are widely and almost unavoidably used in trusted environments. They are also relatively simple.

With ffmpeg, anyone who knows anything about secure application development in the past 20 years knows that it is a huge security tarpit and throwing it untrusted inputs in trusted environment is asking to be owned. You thoroughly sandbox that shit. That’s true for all untrusted media conversion, but absolutely with ffmpeg.

The coreutils rewrite was shit because of the license change. Most of the other founding ideas were also bad as you say, but the license change was absolutely a much worse signal. Just a bunch of people rolling over and showing big corps their belly. And for what? So they can be more exploited by people that treat them like cattle.

Rust does not do "nothing" to prevent logic errors. On the contrary, its strong type system makes them much less likely than in C.

Also security isn't the only reason to prefer Rust to C.

But I do agree ffmpeg would see a much bigger benefit from being written in Rust.