This was previously discussed.

https://news.ycombinator.com/item?id=48623347

Screeching both (both for and against) ebikes in the comments notwithstanding, the highlight is that the increase is largely independent of vehicle size. By the study's own admission they estimate that ~10% of the effect comes from vehicle size.

Watching this ping pong around the various media outlets with titles seemingly inverse of the study's conclusions and watching people share it and comment based on assuming the title is the beginning and end of it really is eye opening.