I am sure that the ' total ripping up and change to Terms & Conditions' are an initial negotiating position - terms and conditions cost money and can be calculated almost as much as actual pay is.
The funders of the railway deficits (i.e. Government) want changes to the terms and conditions. They don't want there to be changes for the sake of them, they wish to save money (in particular to bring conditions more in line with general practice outside the rail industry, and to increase productivity especially where there are restrictive practices), and to eliminate conditions and restrictive practices which impede the efficient and reliable operation of the railway, for the future.
Are railway staff trying to act like King Canute and holding back the tide of such changes which have already engulfed most other industries in one way or another ? Do they really think that Railway terms and conditions are going to be a taxpayer funded outlier for ever? No, they are going to be circumvented or plain eliminated. So how about a road map (ironic that it is described as a road map rather than rail....) breaking the deadlock by embracing the changes, costing these up and negotiating the best pay and conditions deal possible? Everyone, on both sides, has their price. Instead of all this negativity of resistance , go for positivity. Yes, it is going to change the job - to many this will be anathema but look what happened to the printers and miners and seamen when they tried to defend the indefensible. Modernise and get the industry into a good position for the future. By all means pay railway staff good money, but in exchange for good productivity and flexibility to run a reliable service. Some people who cannot keep pace will leave, but others will be there to take their place. I realise that this is going to crash all sorts of cosy arrangements and work/life balances, but the current situation is not financially sustainable. The alternative is decline.