I think the poster child of going full OOP (that one can look at) is ACE/TAO [1], an implementation of CORBA. It had deep inheritance trees and abstractions pi

I think the poster child of going full OOP (that one can look at) is ACE/TAO [1], an implementation of CORBA. It had deep inheritance trees and abstractions piled on abstractions. Similar to Mach and microkernels, folks ran ACE/TAO and thought CORBA was slow, when it was just the implementation that was not built for speed. 1. https://github.com/DOCGroup/ACE_TAO https://github.com/DOCGroup/ACE_TAO