Oddly I knew about 45015 before I really got back interested in railways. It has quite a reputation online with many mentions across various forums. Perhaps part of the appeal is the rough cosmetic appearance, or the notion that it was struck off service one day and parked up there the next as a sort of time capsule?
I suppose there is a 'so near yet so far' element to the engine. There is a yearning to see things like this put right, even if it is almost impossible to do so. I've seen the same thing within the aviation community: The lost cause aircraft tend to kick off a lot of discussion on forums if they are tantalisingly out of reach. The same marque of aircraft might be commonly preserved elsewhere. For example there are B-29 bombers in the US sitting on poles at various airforce bases, stripped of their internals and engines. Nobody cares about these! Show them the top six inches of a B-29 poking out of a lake in Alaska, or in a forest clearing somewhere in the Pacific, and people get far more excited. You could take one of the former B-29s down off a pole and, with a wee bit of work, bring it back to a cosmetically pleasing condition. The notion of returning these things to the air isn't impossible. The aircraft in the middle of the jungle is scrap metal, yet people hatch all sorts of plans for recovery (at vast cost).
In the UK there is an Avro Shackleton in the MOSI in Manchester with an uncertain future. It is possibly the cleanest surviving example as it has been stored indoors since acquired. Conversely there is another Shackleton dumped at Long Marston airfield. It was never fully assembled onsite, has all sorts of issues structurally and is beyond any sort of realistic restoration. The latter aircraft is endlessly discussed on forums, with plans for restoration always imminent, whereas the former aircraft never raises as much concern.
Likewise there are probably numerous other diesel locos of a similar age to this dead Peak that deserve more attention and forum inches, but it won't happen. If 45015 can't be restored and can't be moved, perhaps the best option is to turf over the top of it and re-route the rails around it.