a payload-class, or pointee-class or “managed-class” is fully aware of the intrusive_ptr instances, like a warrant, where the issuer (say IBM) is aware of how many warrants are out there.
a managed-class is unaware of the shared_ptr instances circling around like sharks (ready to KILL it), a bit like an option — IBM doesn’t know how many IBM options are out there.
shared_ptr is also like a Fan club for a celebrity — celebrity doesn’t know about the fans.
“Payload” is clearer in a phone conversation.