One of my favorite stories/theories is that Yoga isn't ancient and Indian at all. It's an originally Scandinavian thing that got exported to India in the 1800s.
Asana is only one specific part of the entire practice. It’s a good beginning point. But it’s also very clear from texts like Hatha Yoga Pradipika, Vasistha Samhita, Patanjali Yoga Sutras, Vajrayana Buddhist yoga texts, and others that yoga definitely isn’t a Scandinavian invention.
Of course, modern Hatha Yoga might have some new poses. But the practice of Yoga itself is quite old, and has been prevalent in India for a long time. (I am not commenting on place of origin, since I am not an expert.)
It's not saying there aren't physical aspects to traditional yoga either, just that the physical practices of traditional yoga didn't fit the needs of the people who pushed the "new" poses.