And yet, I interviewed 10 people easily where I was using new and delete in the example code and only one person asked "hey - can we use unique_ptr?".
A codebase can use only std::make_unique() to allocate heap, and still pass around raw pointers to that memory (std::unique_ptr::get()).
The real problem is data model relying on manual lifetime synchronization, e.g. pass raw pointer to my unique_ptr to another thread, because this thread joins that thread before existing and killing the unique_ptr.
If it's done as part of a "here is legacy code, suggest ways to improve it" question one should point it out, though.