You seem to be saying that we should vote Yes to AV because if we vote No, people will employ fallacious arguments about the meaning of the vote. How does voting Yes guard against this problem? Particularly, why do you think that Yes to AV means yes to reforming the civil service, Lords reform, or participatory budgetting? Surely that connection is just as fallacious? No to AV means no to AV, not to anything else. Yes to AV means yes to AV, not to anything else. (Well, unless it actually means yes to PR, of course...)