That's true, but it doesn't mean C++ is harder to learn. Rust has a broader and more novel conceptual surface area than C++. This is what influences difficulty, not memory safety guarantees.
I postulate that a lot of folks confuse ‘easier to learn’ with ‘easier to get code to compile’ and I disagree that the two are the same. Rust makes it more obvious sooner that you have soooo much to learn.