It would be extremely wasteful to de-vinyl, repaint fleets of trains and refit thousands of railway staff with new uniforms - to prove what? That doing that will 'make things better'?

I'm not usually one to advocate change for change's sake, but some rebranding is inevitable and should be done quickly, but not from TfW to
GWR▸ so close to the end of the franchise as we know it. The Big Bang will come as the first services are readied under our new transport flagship, Great British Railways.
The first step is new uniforms for public-facing staff to show that there is a difference, even if it's the only sign of one. That will have to happen one day, so may as well be done soon. British companies should make and supply all the kit.
For rolling stock, prudence should over-ride eagerness. I'm sure we call all manage with the trains still in the old livery, as we have many times before, until a need for change arises. Relatively small things such as safety cards, maps, displayed posters etc can be stuck over the previous livery until refurb time comes around, with exterior vinyl being replaced as and when trains are due for a refresh. For stations, the same sort of minimalist approach will suffice until major overhaul becomes necessary - after all, it's a railway station. Nobody is going to confuse it with anything else just because it still has an old company logo somewhere.
If my own experience of such matters happening in government are anything to go by, the uniforms will be issued first to anyone working all day every day in windowless offices on the uppermost floors of a high-rise office block. They will have been ordered from Temu or Shein, and because they can't be exchanged in the case of minor cosmetic issues because someone at
DfT» didn't read the small print, the government may find it cheaper to change the name of the organisation to match the new "GRATE BRITTISH RAILWAY" corporate dress. A station newly refurbished or with the paint just dry after a billion-pound rebuild will be the first to be repainted in the wrong colour, followed by the newest train on the network. After months of cancellations because of more trains than usual being repainted, a strike will be announced in time for the start of the World Cup.