Someone once told me somewhere, that if I am trying to learn rust, I should learn C first, so that I know how to shoot myself in the foot, learning to avoid doing so

This is stupid advice. If you want to learn rust then learn rust.

So thats what I did (somewhat) for the past 6 months. I wrote some stuff in C

In that time you are no closer to learning rust. If you started with rust you would know it by now. Rust is not harder to learn then C. If anything C is harder to learn as it's compiler doesn't guide you at all.

You don't need to learn C to appreciate the borrow checker. I find beginners just accept whatever they are first taught. It is only really those that come from C the put up a bigger fight when learning rust.

And 6 months in a language without a borrow checker is not really long enough to learn the reasons why a borrow checker is useful. Not without a good guide that focuses on that. Which most c books don't. The best way to learn it is with rust that actually tells you when you mess up.

The fact that people treat Rust like it's very difficult is odd to me. I write Rust because C was too hard. Lol.

I tried to learn C, but once the learning materials got into double pointers and void pointers, I stopped being able to follow it. So I went back to Rust and after about a month of practice, I no longer struggle with the borrow checking rules (usually the hardest thing for people new to Rust) and it just keeps getting easier over time.

If you know C, you're probably more than well prepared for Rust.

if I am trying to learn rust, I should learn C first

Bullshit. I learned C++ instead of C and I don't regret it. One step further and you should learn assembly, or the electronics powering the computer. Learn whatever you want.