[sseagull]

I disagree. I'm a scientific programmer working mainly in C++ and Python. Deleted and defaulted functions help a lot by reducing the amount of code that needs to be written, maintained, and debugged. Rvalue references help by reducing unnecessary copying, which is a huge benefit when working with large data structures. Before, the workaround was classes that wrapped pointers with shallow copy semantics, which turns into an aliasing nightmare.

YMMV, depending on your field, of course.