Our Matrix Traffic and Transport Data February survey on the Bicentennial Bikeway produced some interesting data. There was a dramatic increase in Helmet use from the January survey. However, nearly all the increase was due to riders bringing their own helmets. This data is from AM peak heading to the city. Therefore you could expect the riders to be "sophisticated" commuters, who have started to plan their trips.
We also saw an increase in private E Scooter usage. Maybe Lime Scooters are a loss leading intro into this new transport mode? Not great for Lime investors, but a great initiative for Active Transport.
A Weekend walk around the Southbank precinct on the weekend revealed that most E Scooter users did not have helmets (Lime or their own). My theory being that these are tourist and infrequent users.