And i've already explained, the ECF and tche multiple studies that they referenced, which were in the TED talk that you showed me, stated that the cause for the drop in ridership in ONE case study in Australia (that was done more than 20 years ago) didn't account for the safety campaign and fear monger that were coupled with the introduction of helmet law. This doesn't mean that the helmet law itself causes a drop in ridership.

You are making conclusion based on a correlation relationship which you don't do when analyzing statistic. Have you actually read the studies that the ted talk referenced? Because they don't actually say the things that the guy in the video implied. Where do you get the statistic that "everywhere where helmet law was introduced, it caused a drop in ridership"? Even the ECF doesn't say that.