As a historical narrative it's pretty shameless, e.g. inventing out of whole cloth a second visit to Frege. I also felt that it did not convey well the personalities (let alone the ideas) of the early analytical trinity.
Indeed. The disagreement over abortion is, roughly, whether killing a human fetus should ever be legal. The disagreement is hard to resolve because it’s not clear which principles to apply, so that arguments pro or con can take on a semantic flavor, but there’s nothing semantic about the underlying issue. (It might be that the author harbors some feeling that all ethical questions are merely semantic; this is putting a lot of weight on a distinction which became discredited in 1951).
The Church-Turing proposition carries an implicit challenge: find an algorithm to evaluate a function which is not Turing computable. Because it can be challenged in this way, it’s not just a definition (mere stipulation how to use the word “computable”).
The remark from Girard may not be so far from some things Wittgenstein said at this or that point. But it's not clear that Girard's remark means anything like that "logic is invented/designed by humans". For example, it might also mean something like what Wittgenstein wrote in the Tractatus:
We have said that some things are arbitrary in the symbols that we use and that some things are not. In logic it is only the latter that express: but that means that logic is not a field in which we express what we wish with the help of signs, but rather one in which the nature of the absolutely necessary signs speaks for itself.