There's a difference between trialing a specific new fare structure
Let's drop the pretence that this is a 'trial' of specific ticket types. It is naked attempt at testing the price and political sensitivity of higher fares, to see whether people will complain enough to prevent the abolition of long-distance regulation.
A real trial would have had a predefined, clearly communicated duration and its criteria for success or failure would have been set out in advance. When responding to an FoI request around the start of 'Simpler Fares', LNER claimed to have no record of either.
and the need to move on from a 41 year old fare structure devised before the internet was invented.
The internet (or at least, TCP/IP which is the backbone of it) was invented in 1983, so if the fares structure is only 41 years old then the internet predates it!
In reality the concept of having a reasonably priced walk-up fare is one that has existed since the railways were invented, so for around 200 years. There is absolutely no reason to move on from that, however old the concept may be.
The notion that the default position of any structure is to go back to what it was simply doesn't reflect changes in society and technology.
Why do any such changes justify the removal of regulated fares? The way that we buy tickets has changed but the fundamental need for affordability has not.
It's not as if the only way you can have affordability and flexibility is to peg longer distance off-peak travel to a specific fare type set in September 1995.
I'd love to see how else you are proposing to guarantee reasonably priced walk-up travel.
If we follow that logic then we ought to be complaining that there should still be one train a day on each route with Third Class fares charged at 1d per mile.
The concept of a Parliamentary train is still very much alive and well. Inflation means that 1d per mile is obviously not a plausible price to charge, but the concept of regulated fares has existed for almost the entire duration of the railways' existence - indeed fares were only unregulated between 1967 and 1995, far less than the duration of regulation before or since.
The LNER 'trial' predates nationalisation and as that becomes a reality it becomes obvious that a TOC trial is a legacy of the 'old' system; what will eventually prevail will be a fares policy developed by GBR that meets the Government's economic and social ambitions. The fact that there is money available for a 'fares freeze' does suggest that there needs to be some visible evidence of prices being controlled.
Why should we trust the railway to mark its own homework? Other countries show the way forward: decisions about fares regulation should be independent of the management of railways. For example, in Switzerland there are countless private railways but all are bound by the decisions of the independent Price Supervisor. Of course, I am sure I will be told that any such arrangement makes far too much sense to happen here...