The Behavioural Insights Team decided to scare people.

From Private Eye, 1-14 Apr 2022, columnist MD writes:

We saw similar things in the U.S., with official and quasi-official sources giving contradictory and flat-out nonsensical advice, all with the overconfident air of science.

Once these behavioural experts get it into their heads that we are irrational and need their guidance, it’s natural for them to slip into offering ridiculous policies such removing the hoops from the local basketball courts.