From a C++ perspective, any block with local variables in it is also basically a struct. And if some of those variables are function objects, then they're basically methods of that struct. So once you make such scopes into first-class entities, they automatically become objects.

This actually happened kinda sorta like that in Simula-67 (from which C++ lifted its object model, for the most part). They started with Algol-60, which has nested blocks, each of which can have variable and function declarations. Since they were interested in simulation of processes, execution of a single such block logically modelled a single process. The problem that they had is that, in a simulation, what you really need is multiple concurrent processes that can reference each other (to pass execution flow around). And so, they made those blocks into first-class entities in their own right, giving the programmer the means to control their lifetime explicitly and to reference them from other blocks - and thus objects were born.