Sky9 asked if there has been a random (say 6) check of other BA 777s HP fuel pumps with a time history the same as the crashed a/c. I hope they have. All mechanical parts wear with usage. If they find much the same wear then this is not significant.
What I would consider is the flow path as to why? the engines slowed to just above flt idle, was it commanded and did the throttles close?, or did the pwr just drift away.
I realise that both the a/p & crew asked for more pwr once they became aware but by then it was too late.
I also note the a/c used 5% less fuel than predicted, on a 10hr flt this is 30mins saved. Unless the on route conditions (w/x) where significantly different this is an almost impossible thing to happen.