Of course there are cases where memory safety issue cause security problems, but not in all cases. If for example by a very uncommon sequence of keypress on my washing machine I cause a buffer overflow, worse case scenario the microcontroller hangs and I have to unplug it and plug it back in again (but hopefully there is a watchdog that resets the processor automatically). A lot of C programs don't even have an user interface, because for example are embedded in device that has no external input (for example a microcontroller that manages the operation of a power supply).
I absolutely agree. There's a class of programmers that would rarely if ever make such mistakes (e.g., Torvalds), and to them, C is freeing.
For the rest of us lesser programmers, the handrails of a borrow checker are necessary.
On the very first run of the port, immediately, I've found a bug due to C weak typing. After a few days, I've found a few buffer overruns.
My take is that there are two types of programmers: those who admit they can't avoid making memory safety mistakes, and real programmers, who don't make such mistakes, and happily keep programming in C/++.
EDIT: Just for fun, I've randomly picked up another C program, written in C17/C18. Immediately found a bunch of problems (not sure if there is any impactful, or not), including inconsistent function prototypes.