The direct attempts at a crackdown failed, and the civil service keeps telling them it can't find any welfare fraud, (which looks fairly unlikely, given certain regional patterns), so they are trying to attack the problem indirectly - by synchronizing the identity numbers of different government record-keeping systems - HMRC, national insurance, the NHS, the land registry, council records.
Strangely there was no fuss when universal child benefit was taken away in 2015 (or maybe later I forget). The media was full of stories about how rich people were getting £20 a week when they didn't need it.
Now apparently pensioners that have a larger income than most working families are desperate for the fuel allowance and they will be freezing to death without it. Its nonsense.