It’s a shame to see such a quaint wee house so ruinous. However, you’re not correct regarding the implications for the building of its listing (nb I haven’t been able to check if it is in fact listed; there doesn’t appear to be a Gurney’s farm/house/farmhouse on Historic England’s register). If it is, I don’t see how you can state that the listing is responsible for the building’s present state of ruination. It’s impossible to say without visiting the site whether it would have been viable or possible to reinstate it for human habitation, so you simply cannot assert what modifications would be required to render it habitable again, and thus whether they’d be acceptable to the relevant authorities. I’ve dealt with many hundreds of listed buildings over the years and the great majority have been perfectly capable of sympathetic adaptation to modern uses without conflicting with their listed status or compromising their inherent architectural and/or historic qualities. In saying that the “person who drew up the listing documents should have been sacked”, you clearly misunderstand the procedures and criteria for listing (see relevant Historic England guidance). Finally, it’s very rare for a local authority to “force an owner to rebuild a listed building”. It did occur when the Carlton Tavern in Kilburn was demolished without LBC some years ago, and the owners were required to rebuild following enforcement action by the LPA and dismissal of a subsequent planning appeal, but such instances are very unusual.