Let's walk this back a bit. Of course the international indices looking at women's well-being and equality do not incorporate data on a country's gender self-ID processes, I never made the case that they did. But it is still perfectly possible to measure this isn't it? You just do a cross comparison of the performance of countries for women against their legal processes for gender self ID and you can easily see what is happening there.
You seem to believe that no analysis on this can be done and no 'gotcha' possible because that was not a measure included in these original indices, but of course that is not the case and it can be analyzed by taking that additional step independently.
So, as we can see, all the major indices looking at women's equality with men and general well-being on multiple measures also tend to have gender self ID in place. Of the three major international indices, the top 10 countries for women in two of these have eight countries with gender self-id processes and in the third all 10 countries have gender self ID processes.
And then comes the question about correlation and causation. But of course I'm not asserting causation, I'm simply pointing out that these countries are able to perform optimally for women whilst simultaneously also having gender self-id processes in place. The burden is on gender critical feminists to explain why, if gender self-ID is so harmful to women, these countries have not fallen down the international comparator tables for women's equality and well-being since introducing gender self ID processes. Because several countries have now had this in place for several years and they have retained their ranking at the top of the international tables for women. They are countries with strong track records in performance for women and why would you think that they are all suddenly now dramatically making bad decisions for women after such a strong track record? And you think all of them have simultaneously lost their minds over this point? It doesn't really add up does it? These are sensible, credible, stable countries, not prone to making whimsical decisions that adversely impact their populations. It is a common refrain on mumnsnet feminism and women's rights that 'how can you support women's rights if you cannot define what a women is?' but of course by their definition all these countries do not know what a woman is and they top the tables for women internationally.
And then you try to make the case that the potential inclusion of trans women data in women statistics would bring these countries up the index ranking but of course this is not the case - because we know that trans women score poorly across the measures in these indices and , if that data is included in women's statistics would marginally bring down women's scores rather than elevating them.
You raise a point that anyone could claim self ID and this is not just feature for trans people. Whilst theoretically true it verges on conspiracy theory to think that large swathes of these (fairly sensible country populations) have people who have M on their birth certificates are, for shits and giggles, suddenly putting down F on tax records, education certificates, and in hospital records etc etc. We know that the number of trans people is stabilizing roughly in the region of 1% or slightly lower, and it is a figure in this region which we can expect the data to be influenced by.
You also hypothesize that I do not consider trans men in the data but of course I am aware of the potential impact here. At the moment we are roughly seeing equal numbers of trans women and trans men, especially in the countries with strong LGBT track records, where trans people feel more comfortable with a certain a trans identity, and which are also the ones that lead the international tables for women's rights. So with this in mind we would roughly expect the influence of trans women in women's data and trans men in men's data to be equal. Both would bring down the overall scores for the sex demographic they were recorded in, as we know that both trans women and trans men as demographics score poorly on wellbeing, educational attainment, employment figures, income, physical health and mental health and political empowerment. They would do this to a similar magnitude resulting in an overall negligible impact on the index.
So we have every reason, because of this, to believe that the trans data in these studies exerts a very marginal overall influence on the overall outcome and ranking on these international indices.
I do myself support the recording of data in both respects, for sex assigned at birth and gender self ID if this differs, accessible make it easier to analyze the data in the future with more accuracy.