It means getting roles that are currently done by humans and getting them done by machines.
For example on LU they introduced Oyster card years ago and eventually they wanted to do away with the ticket staff they had in the ticket offices as everyone was using oyster or a ticket machine. When Bob Crow found out what TFL were doing he threatened major strike action. From talking with people who work on LU I found put a "compromise" was reached to transfer the ticket staff into newly created roles called station supervisor's which sat between a CSA role and station manager.
The ex ticket staff ended up getting a bump in pay and the the Mayor of London (may have been Boris not sure though) got to say they got everything they set out to achieve. An absolute nonsense and farce, no wonder LU is so expensive.
Train travel will never be price competitive in this country if we don't embrace change and just allow insider corruption and union coercion to continue.
While the TFL ticket office is a good example of where unions might be overstepping (there's still a number of oyster services that require staff intervention), to blame them for the cost of train travel or even suggest it might be part of the reason it's so expensive in this country is very disingenuous.
TFL and it's managed decline under the tories is a great example of how government intervention, or a lack of it, will ultimately make rail travel more expensive and provide a poorer service. The government are forcing TFL to become completely dependant on revenue, virtually every large metro system in the world receives a government subsidy, even in the US where public transport is rarely a priority. To do it after a pandemic where passenger numbers still haven't recovered is even more moronic. It's not a coincidence that this is happening to one of the few publicly owned transport orgs in the country. As a result of this they've already been forced to cancel several projects to improve lines and accessibility, revenue streams like the congestion charge scheme are being forced to expand, and (this one surprised me) they've added restrictions to the freedom pass for elderly people. No doubt that ticket prices will also be forced to increase too. So government meddling in this instance results in a poorer service and higher cost, all nothing to do with unions.
Modernisation is a blanket term and it seems the politicians rolled out to repeat it have succeeded in making it an argument against unions. From the documents i've read from unions, they're generally in favour of 'modernisation' but not at the expense of safety or staff numbers. e.g. They'd probably support driverless trains, but not if it meant zero staff on board. Thats partly where the ticket office pushback comes from, the unions see it as a precursor to unmanned stations. The number of machines doing human jobs (specialist track inspection trains, helicopters capable of track inspection, track-building machines etc. etc.) and the amount of new equipment trials I see network rail carrying out really fly in the face of all this anti-modernisation chat, at least to me anyway.
I also really struggle with the idea that we allow foreign companies to run our train-lines, most of which are actually nationalised, at least partly, in their respective countries so we're effectively subsidising tickets in other countries.
But nah it's probably unions making rail travel so unattractive in this country.