> I think the actor model comes closest to Kay's objects.
It's rather the other way round. There is no pre-Hewitt implemented semantics matching Kay's later 2001 claims; Smalltalk-72 was a synchronous token-stream interpreter rather than a system of independently active message-driven agents; FLEX shows processes, scheduling and quasi-parallel control, not objects, not messaging, not actor-style autonomous entities.
Actors are great, but it’s just making objects large enough so one thinks carefully before architecting a whole hierarchy of them to solve a simple problem.
As someone else said in this thread, OOP is fine for modularity, the problem is people don’t know how modular a problem should be and are driven to overcomplicate the design of any application.
It's rather the other way round. There is no pre-Hewitt implemented semantics matching Kay's later 2001 claims; Smalltalk-72 was a synchronous token-stream interpreter rather than a system of independently active message-driven agents; FLEX shows processes, scheduling and quasi-parallel control, not objects, not messaging, not actor-style autonomous entities.