People often forget that 10X does not (only) mean quantity, but most of all quality.
Also thinking in factors may not be the right approach here. We should look at it in a more binary way: Can a developer achieve the requirements or not? In most cases the magnitude of skill shows in what a developer can solve at all, not how fast he/she can solve it.
Memory safety issues are bugs. Do you know any programmer that does not occasionally create bugs? Don't forget tight schedules, low budgets, ...
Also rust is just what you propose that - a programming language integrated with heavy verification of safeness built-in. Because occasionally someone writes c code without using all available tools to verify the code it is better to have it built in.
Memory safety is not an issue if you actually learn to take advantage of the C toolchain. I've caught memory leaks and buffer overflows to great effect just by using Valgrind and ASAN. And for most applications, you can limit the attack surface by only writing C for the performance-sensitive areas and using FFI to call into those routines. As a bonus, it becomes much easier to unit test for logical corner cases.
This just isn’t true in practice. Can you point to a popular c project that’s accomplished this? I bet there are a few tiny ones that make such claims but haven’t received scrutiny.
No it's like you leasing your house. Selling the house to a third party. One party (your buyer) owns the house. The original owner also owns the same house, since he only leased it to you.
But houses are non- distinguishable. You don't need to give him back exactly that house, just an identical one.
Also thinking in factors may not be the right approach here. We should look at it in a more binary way: Can a developer achieve the requirements or not? In most cases the magnitude of skill shows in what a developer can solve at all, not how fast he/she can solve it.