Little by little, Rust, like D, acknowledges that C++ flexibility regarding object construction, copy and move, even if too much as a default, is sometimes needed :)

I saw in D years ago how they also checked into this flexibility after getting some use cases for it (in this case, copying): https://github.com/dlang/DIPs/blob/master/DIPs/accepted/DIP1...

This is the opposite, it is further opting out of flexibility.