Does making Youtube videos improve your CV?
Universities are usually interested in the degree to which their teachers can gain wide recognition for their teaching, and thereby spread the reputation of their institution.  If you are able to publicise your teaching work to a wide audience, this enhances the reputation of the institution you are in, and so the university has an interest in that outcome.  Universities like their academics to be in the public-eye, since this adds to brand-recognition of the university, and shows that their academics are influential in the public sphere.  Hence, any activity which gains you wider recognition for your teaching or intellectual work is going to be something worth putting on a CV.

A useful case-in-point for the potential career value of academic YouTube videos is the case of Prof Jordan Peterson at the University of Toronto.  Peterson was a successful academic in a Canadian university, but was not widely known outside his field until he began producing YouTube videos of his lectures and his general thoughts on social issues.  Coupled with him taking on some controversial topics, his use of direct communication to the public created a great deal of interest in his work, which has led to him being widely featured in conferences, interviews, etc.  Two years ago I hadn't heard of Peterson;   six months ago he was described in the New York Times (albeit second-hand, with agreement) as "the most influential public intellectual in the Western world right now".  This is an extreme case, and it is also influenced by the social topics that Peterson discusses, but I think it is fair to say that if he had not produced YouTube videos, his work would not have spread as widely.   So yes, YouTube videos of your teaching can make a difference.