Well, it mentions classes, for example. The opcache handles that already, cross process. For a live object, people tend to use apcu. It's not as nice as a shared object across 2 couroutines, but it's reasonably fast because it's using mmap and fairly fast serialization to share the object.

So, what they are proposing is helpful. But, they seem to be assuming that PHP shares nothing across processes. That's just not true.