I've seen this idea from a few people and I don't get it at all.
Rust is certainly not the simplest language you'll run into, but C++ is incredibly baroque, they're not really comparable on this axis.
One difference which is already important and I think will grow only more important over time is that Rust's Editions give it permission to go back and fix things, so it does - where in C++ it's like venturing into a hoarder's home when you trip over things which are abandoned in favour of a newer shinier alternative.
Rust is certainly not the simplest language you'll run into, but C++ is incredibly baroque, they're not really comparable on this axis.
One difference which is already important and I think will grow only more important over time is that Rust's Editions give it permission to go back and fix things, so it does - where in C++ it's like venturing into a hoarder's home when you trip over things which are abandoned in favour of a newer shinier alternative.