I think there are certainly different complications in Rust than C++. The RAII can be roughly the same in the naive sense, but there's having to worry about Send and Sync and Pin and fighting with the borrow checker and all that fun stuff.

Gauging how "complicated" a language is somewhat subjective, so it's kind of hard for me to give a straightforward answer. I think it's certainly easier to be (some definition of) productive with C++ than with Rust. I feel like to do anything even remotely non-trivial with Rust, you kind of have to understand everything, because if you don't do it in the "Rust way", it often won't compile. I think this is a good thing, but it does make it harder to get started.

C++ has a lot less consistency and (kind of) more features, and lots of strange semantics to go with those features, and so if people actually use them it can get confusing and hard to read pretty quickly.

My knowledge is a bit out of date, to be clear; previously whenever I need something in the C++ domain, I could fairly easily just reach for C and use that instead. Now Rust is available and I think overall better (though I do sometimes miss how utterly simple and dumb C is).