The assumption with this line of thinking is that trans women don’t inherently belong to that class of participation

I don't think it's right to call it "an assumption". By definition, a restricted competition class uses rules to establish who is allowed to participate. These rules are willfully and intentionally composed. When circumstances arise that make the rules ambiguous in some way, the participating community is called to clarify them.

This isn't unique to women's chess, it applies to any restricted class sport or competition.

But following this analogy through, you’re not asking all PoC. You’re asking the majority of the subset (for example, black participants) whether a minority of the subset (for example, Asian participants) should be allowed to participate or not.

To be clear, I am not in any sense telling the chess world, much less women players, how to set the rules for their restricted class of competition. I am saying that women chess players are stakeholders in the rules of women's chess. Precisely how their input is to be converted into a decision is not in my scope of understanding, and it would be presumptuous of me to hazard a guess at how they prefer to operate women's chess.

The decision is already made, and pointing to the remainder to justify the decision is working backwards

Agreed, and that was not my intent.

I genuinely don't how or if women chess players were involved in this decision, I'm only responding to the assertion that asking "what cis women think about playing trans women" is morally equivalent to asking racists whether they want to play against black people. It paints current women players with a broad brush and disenfranchises them from the management of their own competition.