The author's "internal_ptr" template seems exactly equivalent to Objective-C (and I assume Swift)'s weak references.

And that's great! Automatic reference counting is my single favourite thing about Obj-C. Once you get the hang of using weak refs for parent objects, ARC is very easy to use, with consistent speed, low memory usage, and immediate deallocation of dead objects.

I'd go as far as to say that Objective-C is a big reason why iOS has historically been faster and smoother than Android. It's not the world's fastest language, but there are no big GC pauses and it doesn't waste a lot of memory.

So I bet this is a good memory management style for C++ too.