Because smart pointers are still pointers under the hood. You're forgetting the time before you know what pointers were - people coming from higher level languages don't immediately grok the concept. By teaching them automatic memory management patterns like we use in C++ without teaching them why you need such things, they'll never fully understand the code they're writing.
It's like the "I know React but not JavaScript" crowd all over again.
It's like the "I know React but not JavaScript" crowd all over again.