The end of internal combustion cars (on new sale) announced for the same date was a non-announcement as technological development means only niche cars (Ferraris, for instance) will have any use for petrol or diesel engines by then. It happens regardless of ministerial announcements. With trains, the technology is also here, but depends on government investment (or a radical rethink of rail privatisation).
That may be so, but there is still a false equivalence being drawn between the last sale of
IC▸ cars and the last withdrawal, of solely IC trains, even more so given the longer lifetime of a train.
But in practice, it's not so different from what the industry has being forecasting. Last year's rolling stock strategy document scaled back the rate of replacement of diesels by electric trains a little compared with earlier ones (and note that in that report bi-modes count as electric). The forecast numbers for 2044 (as at 2015, pre-Hendy) or 2046 (as at 2017) were:
2044: 1234 diesel out of 22031 (6%)
2044: 2460 diesel out of 21136 (12%)
(both are the middle of three forecasts for different levels of increase).
Both forecasts assume that every diesel engine not meeting NRMM IIIA or B will never be replaced, and all such trains (i.e earlier than classes 800 and 68) will be scrapped before then.
So on that basis the industry is likely to say "So? What's the problem?".