As far as I can tell, I agree with what you say—this seems like a good account of how the cryptophraher’s constraint cashes out in language.
To your confusion: I think Dennett would agree that it is Darwianian all the way down, and that their disagreement lies elsewhere. Dennet’s account for how “reasons turn into causes” is made on Darwinian grounds, and it compels Dennett (but not Rosenberg) to conclude that purposes deserve to be treated as real, because (compressing the argument a lot) they have the capacity to affect the causal world.
As far as I can tell, I agree with what you say—this seems like a good account of how the cryptophraher’s constraint cashes out in language.
To your confusion: I think Dennett would agree that it is Darwianian all the way down, and that their disagreement lies elsewhere. Dennet’s account for how “reasons turn into causes” is made on Darwinian grounds, and it compels Dennett (but not Rosenberg) to conclude that purposes deserve to be treated as real, because (compressing the argument a lot) they have the capacity to affect the causal world.
Not sure this is useful?