I've just had a reply from Rubycup:
thanks for taking the time to write to us.
Gender inclusive language doesn’t mean that we don’t ever use the terms women or girls, instead it means that we acknowledge that not only women and girls have periods. Just as saying “black lives matter” doesn’t mean that no other lives matter.
By trying to be more inclusive and gender neutral in our language, we’re not harming anybody, but simply trying to include all types of ways of how menstruation is experienced.
However, when we talk about our donation program we use words as "women" and "girls".
We work closely with locally based partners in order to create a donation program that is tailored to serve each community’s needs. It is through listening carefully to what they want that we can support them to deliver sound education on reproductive health and menstrual care so everyone can live their periods with dignity, free of shame. This listening includes adapting the language we use to talk about our donation program.
We/our partners work primarily with students in schools where using a like term menstruator will be more confusing than helpful. The objective is to help them understand and know their own basic anatomy and how periods work - this is already a lot to cover and grasp.
Moreover, it took a lot of time for our local partners and organisations (like Golden Girl Foundation or Femme International) to sensitise the society to invest effort in girls and women (meaning, convincing parents and schools that it is worth it to spend money on their education, uniforms etc and allow them to do homework instead of helping out at home etc). So in this context, using the word “girls” is very important.
Gender identity is beyond the scope of our expertise right now. Though we don’t exclude it as a part of our menstrual health education program in the future.
Menstruation is a topic that is evolving as beliefs and values change. We are working to do our part to change attitudes about periods and look forward to a day where we can be more inclusive in our language wherever we are in the world.
Thanks again for your message.
Kind regards,