I haven't seen the 'castle' shot and so am not making any comment about that at all.
However, I have been to galleries as viewer and have stood 'admiring' stuff whilst a gallery sales person near me has been making a pitch to a client. I can't believe the bullshit from the selling mouth would ever be offered to a person who actually knows anything about the photographic process and what makes it tick. To me, then a working pro, it was insulting - to say the very least! If you can, have a look at Jeanloup Sieffs eponymous, epic oeuvre from Taschen, finished just before he died; in it, despite the myriad shows the man had, you can read his own views on the gallerists in the original French... not flattering.
Whether to make it in the gallery world (if one wants to) one does or does not need to do all the things suggested in various posts here, I can't say; what I would say, though, is that I don't really see the sour grapes thing having a lot to do with it. Neither do I think that, in general, the photo-as-art market is mature enough (outwith the USA) to have had much of a history. I started off as a pro in '60; nobody I knew had ever heard of photographs as art; some High Street outlets like Athena began to sell a few images, but they were at anything but gallery prices. By '66 I was in business for myself (advertising and fashion) and still hadn't the slightest idea that photography would become a money item as art. In '81 when I left the UK I sold off what negs and trannies clients wanted and destroyed most of the rest, keeping only a very few images to which I was personally committed for my own reasons. Had I thought that fashion pics would one day be valuable as art, I'd sure have clung on to what I had. Sadly, the 60s ain't comin' back no day soon, and all that stuff is gone forever from my files.
So, my point, really, is that I believe that only someone young today is going to be in a position to think of art photography as career. Or someone whose stuff was held (with luck) in Vogue, Harpers and Elle offices for many many years!