In theory it's the same legislation, but it is ridiculously more difficult to bring a private prosecution, so in effect they just don't happen.
In Scotland, you need to get permission from the High Court (the supreme criminal court) to even bring such a prosecution. The general view is that it will almost always be denied unless there's truly exceptional circumstances. The High Court has quite consistently held that the Lord Advocate has primacy when it comes to prosecutions, and the High Court also has the view that a mistake by the Crown is not enough to warrant exceptional circumstances, although the door is still open if the mistake was "extravagantly wrong". Having said that, even where there is strong evidence that the defendant is guilty, the High Court has refused permission to bring a private prosecution.
In general, you need to spend quite a lot of money to even apply to the High Court, although it is the case that both the Justiciary Office and the Crown will support applicants with whatever they need to bring the application. Usually the case will be held by three of the most experienced and senior judges in the High Court, and if the Lord Advocate opposes the "bill for criminal letters", then it's almost certain that the High Court will deny the application. In practice, there have only been three successful applications since 1900, and the prevailing view among many in the Scottish legal community is that it's time for them to be completely banned as a relic of legal history.
I've never witnessed an undiscounted ticket sold outside of peak times, nor seen a UFN issued.
Scotland is in general much more pragmatic about fares. I was once throwing my guts up from a nasty case of the flu and I just wanted to get home, and I managed to lose my ticket somewhere between Liverpool and Glasgow. I got to Queen Street after throwing up twice on the way, realised I'd lost my ticket. I asked the guard on the last service to Aberdeen if there was anything he could do because I just wanted to get home, I explained the circumstances and had to break off to be sick yet again. He took one look at me and said "get on" and left me to my misery. When we got to Aberdeen, I asked him how I could pay the fare, and he said "don't worry about it, you wouldn't have been travelling in that state without a ticket" and wished me a good night.
Generally speaking though, Scotrail are much more pragmatic about actually making sure that people are checked and tickets sold.
The difficulty with pure yellow cards is London. Very rare to encounter a fare check outside of certain well known spots. Still plenty of places (aside from tube) you can get on/off without a barrier. Why would someone dishonest pay if they hadn't had a yellow card in the last year? It's also somewhere where there are many parts of the population that would find acting like that acceptable, even admirable. There needs to be some sort of fairly heavy financial disincentive given the likelihood of getting away with it.
The simple answer is to increase the amount of ticket checks. Of course there are many such places, but then the TOC should be contractually obliged to carry out checks onboard and at stations. If people knew their tickets were going to get checked on 9 out of 10 journeys, it changes things considerably.
Wouldn't be too difficult to make a database where such interactions were recorded, along with any action taken.
Yes, it would be enough to simply record that the person has received a 0 pound fine. The system can easily be set up so that any RPI can see at a glance what they've previously been caught for. All of those things mentioned in your quote are sensible and pro-passenger, and without a national ID card, it seems like a good compromise. Of course, it doesn't deal with those who are confident enough to give a fake name and address, but that's a country problem rather than a TOC problem.