Who was harmed, so why care ?
This is what many will think, including those at the electoral commission. But it is clear that China thought that putting the effort into getting the data was worth while.
The consequences for some individuals could be great, I read stories on how China issues threats to people in England who have relatives in China.
The consequences for those at the electoral commission will be receiving a memo on security that most will not bother to read.
There is also the notion that as they have now fixed their Microsoft Exchange that all the harm is undone and there is no need to worry. Not true: China still has a list of all voters in the UK and much of the information will not change for years (when did you last move house ?).