Do we though? When was there last a train crash, as in train hitting another train or derailing with significant loss of life?
August apparently - although nobody was hurt.
https://en.wikipedia.org/wiki/List_of_rail_accidents_in_the_United_Kingdom
Although with a slightly different parsing of the question (OR/AND/NOR/NAND would be so much more helpful than commas and conjuntions sometimes) would mean going back a while - most of the accidents in recent years seem to be in stations/on crossings and not that many fatalities, although even the incidents with a single death are pretty singnificant to that person, I reckon. It looks like you have to go back to Potters Bar in 2002 to find a crash that caused multiple fatalities AND specifically involved (multiple trains OR derailment).
When the ECML service was briefly re-nationalised (because it was a bit of a wreck) rather than run for profit their performance measures (trains on time etc) improved dramatically. Staff at the station, as well as being more bike-friendly that before and since, seemed a lot more cheerful too - and I think I read that it even turned a profit for us all. Shame it got handed over to the beardy one once it was back to functioning properly really.