He is a leader and a political figure. This blogpost is political (as well as sharing a family photo, which is itself imbued with a political message in that context).
Engineer archetypes hate politics and refuse to think about it. For most engineering, there is negligible political dimension. But culturally-transformative technology is inherently political to the degree it's transformative. Altman recognises this.
He is working towards a social goal, and attracting support to achieve it. Yes, he is a political leader.