[pornel]

To me it was the opposite: it gave me a vocabulary and taught me how to think about these problems.

Shared mutable state and ownership exists in C, but I just don't get any compiler support for it. I can't even document it in code, so I (and users of my libraries) rely on RTFM.

In C I'd just "wing it", and tweak the code until it stops crashing. Maybe add a flag with "obj.free_data_ptr = true" and keep adding mutexes or copies of data where I suspect it's necessary.

In Rust I get predefined templates for this — owns & borrows, cells/atomics, refcouted and mutex containers, etc. The compiler says "nope, this is wrong!" and I get to conciously decide how to solve it — do I share or copy the data? Is the sharing dynamic, or just in a wrong scope? And my decisions are documented in code, and enforced by the compiler.