Very insightful post
@Enter Valhalla; a post that I also agree with quite a lot of.
It might also be worth noting; I certainly don't think BPB had plans to close Wild Mouse at all. For starters, they invested in a new braking system or something like that less than a year before it closed; they wouldn't have done that if they'd known it would be closing. Also, I think the Thompsons do care about the park's heritage; I remember reading a news article around when the Mouse closed saying that Amanda was "in tears" at the prospect of having to demolish the ride.
Furthermore, as you said above, people are trying to get better value for money out of days out in this day and age. If BPB had stuck to free entry and pay-per-ride, the amount of rides the average guest does in a day at the park would likely end up costing far more than the £39 (I think?) that a wristband costs, and that's on the day! At present, there are 43 attractions in the park, and that's excluding the entertainment, so with the on-the-day cost of the wristband, the cost per attraction is approximately £0.91. Compare that to when the park was entirely pay-per-ride in the 1990s; even back then, 1 ride on the Big One cost £4 (taken from the BPB documentary aired in 1997), which when adjusted for inflation comes to £7.22 in 2019 money. The other rides cost £2, which is £3.61 in today's money. So even if you were to only have one ride on each of the 10 coasters (I'm presuming that Icon would also cost £7.22 like the Big One, as they are currently the same price), it would set you back £43.32; £4.32 more than the wristband giving you unlimited access to all 43 rides in the park. So in theory, the park has become substantially better value with the introduction of the wristband. I'd imagine that 90% of visitors to Blackpool use the wristband now, as the park definitely seems to be positioning themselves to be more of a day out.
As for the introduction of the entrance fee, I think it was a good decision. I thought that BPB had an incredibly pleasant, classy and family-friendly atmosphere when I went for the first time last year, and my family seemed to agree. However, my mum visited in the late 90s when entry was free, and she did not have positive things to say about park atmosphere based on her visit back then; she was very pleasantly surprised by how much the park had improved in this regard when we went last year, and she thinks this could be down to the entry fee. Also, wasn't Blackpool in quite a bad financial situation in the 2000s, so wouldn't it have been a decision to ensure the long-term future of the park?
As a final point, it might be worth me noting that Blackpool as a whole has likely seen a decline in visitor numbers. We now live in an era where discount sites like Skyscanner as well as various low-cost airlines can get you to a sunnier seaside destination in a country like Spain for less money than it costs some people to get to Blackpool in petrol. For that reason, less people are visiting Britain's seaside towns as a whole than 20 years ago, so BPB have to adjust to this and market themselves more as a standalone park than they did back in the 1990s in order to attract custom.