Having recently come across and joined this forum, perhaps I can make the following observations.
1. Any organisation, whether in the public or private sector, exists to produce a product or provide a service, at a price and to a quality that other people are prepared to pay for. The organisation does not exist to employ people.
2. Since the major funder of suburban rail services tends to be the Community rather than the fare payer (quite rightly), the public purse decides the price and quality. The railway is not and never could be a worker's co-op.
3. The fundamentals of the job description of guards, and many other railway staff, date back around 100 years, to the days of thousands of mechanical signalboxes, carriages without through connections etc. It is inconceivable that much of this is appropriate in 2017.
4. If the passengers were asked to draw up a job description for the passenger-facing staff they rightly want, it would, I believe, bear little relation to the Traditional Role of the Guard, and much more to what Merseyrail want them to do.
5. Given that the network is almost entirely self-contained, I am surprised that the new trains have driver's, this being the most easily automated job in the system, as has been demonstrated all over the world, including in the UK.