First, I agree with the stance taken by singletrack and their decision to be vocal (albeit in a very limited way) about it, so credit to them for that.
Secondly, threads like this are an excellent way of exposing just how pervasive and unthinking everyday sexism and misogyny continue to be (and by-the-by allowing monumental bellends and the sadly feebleminded to out themselves) so long may it continue.
The problem I have with the video is mainly the role of the women in the video, what they are doing. They do nothing and contribute nothing to the content of the video. They are (literally) a backdrop, incidental to the action. As such they are reduced to the level of scenography, of objects. Conceivably then they could be replaced by anyone (or anything) and the video could be shot exactly the same and remain of more-or-less the same interest, value, or meaning. That they are there, appearing as they appear, and doing what they do is therefore telling . Even more so when (AFAIK) they are the only women to appear in any of Macaskill’s many videos* – suggesting that that the version of womanhood represented here is the only one that is valued.
The video, as many others have said above, implies that biking is something that men do, and if there are girls around then their role is to watch (and ideally look pretty). It constitutes a narrow vision of how women ought to appear and behave, and offers an image of cycling that I don’t want to be associated with.
*apart from his mam’s voice in Imaginate (?)