It sounds like you’re suggesting that inventing grammar is the convergent result of a general competency?
There are some caveats, but more-or-less, yeah. E.g. the language-processing parts of the cortex look pretty much the same as every other part of the neocortex. E.g. some people talk about how language is special because it has “recursion”, but in fact we can also handle “recursion” perfectly well in vision (e.g. we can recognize a picture inside a picture), planning (e.g. we can make a plan that incorporates a sub-plan), etc.
There are some caveats, but more-or-less, yeah. E.g. the language-processing parts of the cortex look pretty much the same as every other part of the neocortex. E.g. some people talk about how language is special because it has “recursion”, but in fact we can also handle “recursion” perfectly well in vision (e.g. we can recognize a picture inside a picture), planning (e.g. we can make a plan that incorporates a sub-plan), etc.