Less dialogue content (as measured by the time of extracted voice lines, which someone extracted and uploaded on yt) and less scenes in comparison to all origin characters. Astarion has simply the most content, so the difference is the biggest.
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Source?
How much less? Perhaps some of the writing conveyed information more succinctly in regards to Wyll's story.
However more to the point so what? How is this evidence of racism? One origin character was bound to be the one with the least content.
