There are a lot of possible explanations for this:
Maybe the people who aren’t interested in AI also happen to vote for more sessions. (At a quick prod at the data, penalizing votes from people who voted for large numbers of sessions does not seem to change the conclusions above, but I haven’t investigated this thoroughly.)
Maybe AI is a more fragmented topic due to its newness, and interest has not coalesced, leading to a large number of small sessions. (But again, •total• votes for AI, including the whole long tail, were proportionally smaller.)
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