Here's the real version of "why are they voting against their economic interest?" and the MSM is strangely uninterested in asking that question. How much time until the last AFAB women plays in the WNBA after the league is open to "transwomen"?https://www.si.com/wnba/2020/10/30/wnba-vs-loeffler-daily-cover …
Leaving aside if voting (D) actually is in their best interest the answer is the same anyway - supporting the team is more important. WNBA players find it more important to support the team rather than protecting their jobs.