I'm not sure what is meant there. "ownership" in many languages is a very real thing to me.
For example in C++ you might create an object and then you have a pointer to it. At some point you have to "free" that object else you have a memory leak.
You might pass that pointer around to other functions and threads in your system. At some point someone has to "free" it. But who? Not necessarily the creator of the object. Hopefully at least the last user of the object, else you have a dangling pointer reference.
One has to take account of this ownership problem when building a C++ program to avoid big problems. Even if the language itself does not have a way to express ownership. Similarly for other compiled languages. Heck, even assembler.