Drona and Eklavya story: Its NOT about Casteism at all!

A lot is said about how Eklavya – a tribal warrior – was deprived off of his archery ability by a Brahmin, Dronacharya.  It is showcased as an example of Caste system.  However, the details from Mahabharat suggest something totally different. Balaji V. sums it up very well, when he talks of