The problem with this question is we're talking about a national politician. If Joe the Democrat from Ohio changed his vote or stayed home in 2016 entirely based on her gender then that could be construed as "being a victim of sexism". However, for every Joe there was a Becky who voted for Hillary due to gender as well. So overall it either balanced out or was a net benefit for her anyway. It did not cost her the election and there she wasn't a victim of any organised sexist campaign.
Clinton lost because her hawkishness, her decades of political baggage and her comments regarding Coal mining and "deplorables" were successfully exploited by the Trump campaign. The people who are spouting the "muh sexist" bs are the usual suspects who are using this as an excuse to vent about the oh so evil and horrible, knuckle dragging, Middle American whites.
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