While this *might* be relatively innocent tinfoil-hattery, it could also be an amazingly cost-effective example of asymmetric warfare (target the most gullible minds with a conspiracy theory that gives them an incentive to vandalize transport infrastructure):
Pensioners attack Devon traffic lights over wild 'deadly weapon' claims
An online movement say that the sensors on traffic lights can cause heart attacks, brain cancer, anxiety and even sudden death
https://www.devonlive.com/news/devon-news/pensioners-attack-devon-traffic-lights-11148748
@cstross Wrecking traffic lights is more likely to kill people than the sensors they worry about. We had the nonsense with 5G towers before. The anti-science brigade are a menace, but some actually have political power these days.