Well if your wishes come true and the DfT reinstate a nasty dated livery from the 80s, I’m sure an update will be provided in the Great British Railways thread as soon as it happens.
Not nasty or dated for those of us around then!
And to be fair it was introduced in the 60s, so it was already well-bedded-in by the early 80s. I guess the 70s was the archetypal decade for blue-and-grey, though as I didn't use the railways then, my memories of it are indeed from the 80s.
But echoing other comments:
NSE was an actual 80s livery and that is rather nice, I think it's a shame that didn't last longer. Also liked the "orange" variant for slam-door-era SWT.
And also, with the newer SWT livery, I always liked the differing liveries for express and slower stock. It was always good to see the 444s and 450s in different liveries - it gave the railway more character and brought through the "express" nature of the 444s far more than the SWR livery.
Didn't like privatisation at the time, but now I'm getting nostalgic for the days of SWT.