And those sites and apps all offer fares based on journey planner inputs, which generate valid itineraries which surely remove even more of the confusion - just follow what it says?
That said, I think some restrictions on off-peak tickets are confusing, or at least very badly worded - to the point of confusing.
However, my theory is that when people say that rail fares are confusing, what they actually mean is they don't (or don't want to) understand why there are different fares available. Why will it cost £25 to travel on the 08:45 train, but only £15 to travel on the 08:55 train? It's actually very simple and logical - the former is an Anytime fare, and is travelling on an intercity service - arguably more comfortable environment, more onboard facilities, less stops and a quicker journey time. The cheaper ticket is a "booked train only" advance, using a local service with more stops, a slower journey time, fewer onboard facilities and an arguably less comfortable environment. It's a concept that most people seem to understand when it comes to airlines - cheapest fare = no frills, no flexibility; higher fare = more frills, more flexibility. Perhaps it boils down to usage? People travelling a long distance are going to want to use an intercity operator and draw comparisons with airlines, whilst people making shorter journeys are more likely to draw comparisons to a bus and aren't massively fussed about whether they get the intercity option or the regional/local option (if such a choice exists for that route)?
I don't think people are genuinely confused by the notion that flexible, peak time, or fast service tickets are more expensive than others. Yeah some people make it a meme to say they can fly to Benidorm cheaper than they can get a train to Manchester or whatever, but those people know what they're saying and are being deliberately misleading.
But rail fares in the UK are confusing.
When I travel from my home in Scotland to where my mum lives in Wales, split tickets can save over 50%. This is just stupid.
26-30 Railcards have a minimum fare of £12 before 10am on weekdays, but TVMs instead of selling an £8 undiscounted ticket will offer a £12 'discounted' ticket. This is just stupid.
16-25 Railcards also have a minimum fare of £12 before 10am on weekdays... except in July and August. So a 25 year old gets a cheaper ticket on their morning commute in the summer, while a 26 year old doesn't. This is just stupid.
Actually age-based railcards are valid for a fixed period at the time of purchase, so a 26-30 Railcard is actually valid until the day before your 32nd birthday. This is also stupid.
The legislation makes it an offence to travel on a 16-25 ticket when you hold a 26-30 Railcard even though the price is the same. This is stupid, to the point that the regulator had to intervene to stop people being taken to court for
criminal offences when the railway wasn't even losing money. This is just stupid.
That's before we even get into split tickets, rovers, GroupSave, TOC-specific group discounts, rangers, regional Railcards, SuperFares, ScotRail Kids For A Quid, Club Avanti, LNER cashback, the fact that mature students can get a 16-25 railcard, Scotland NEC, Unizones, GTR money back guarantee, XC feeless Advance ticket changes, PlusBus, Nothern Duo, gold cards, RailMaster, Rail & Sail, flexipasses, GA pregnant passenger first class upgrades, SeatFrog, carnets, season tickets, flexi passes, etc etc.
It's an absolute farce if you ask me. And no level of Boots-level sales assistant is going to solve this, not least because the guidelines say not to proactively offer e.g. split tickets.