When there's a choice between conspiracy and incompetence I generally go for the latter. In this case I suspect the people making the decisions really aren't aware how difficult/impossible it sometimes is to get a TVM▸ to sell the cheapest (or best, even if it's perhaps not quite the cheapest) ticket and I don't think ticket office closure is deliberately designed to increase revenue in that way.
I suspect you are correct on this. I have got to know quite a lot of rail industry professionals over the years, and almost all of them are good, but most of them travel on staff passes or have a transport department.
Not exactly a "mystery shopper" job, but I would love to see a senior politician or
DfT» civil servant dropped off at Melksham Town bridge and be required to make the journey to their office on Horseferry Road and back frugally. They might find it very educational, especially if not provided with a smartphone (but we will let them have a credit card). An artificial test for sure - perhaps better if the candidate were to be that person's mother, son, or ex, shadowed by the VIP but not helped through systems.