Stonewall is an utterly poisonous, corrupt racket. Because they once had a good reputation for gay issues and became a partner for government, business, universities, the public sector, etc. that were looking to develop pro-gay workplace policies, once same-sex marriage had passed in the UK and the gays apparently had no needs anymore, the trans swept in and captured Stonewall and used it to relentlessly promote their trans/gender ideology.
They were hugely active behind the scenes and under the radar, with their trans workshops (brainwashing programmes). With the Diversity Champions programme and the suchlike , Stonewall convinced government, companies, the NHS, the public sector, etc. they could simply outsource their policy-making and diversity training to them, get a nice little Diversity Champions award and also that way they would attract the active and voluble so-called "LGBTQIA++ community" as voters, customers, etc. In reality, they have made life a hell for gays and, especially, lesbians.
Don't underestimate the pernicious effect of this disgusting cult-like organisation on public life in the UK. They are responsible, through their workshops and guidelines, for this sudden onslaught of crazy gender ideology policy in the UK in recent years, from single-sex toilets and gender ideology promotion in schools, to the introduction of insulting language in the NHS ("people with cervixes", "chest feeders") and men in women's hospital wards, to male rapists in prisons, to the ridiculous contortions the Labour party has got itself into. And people are too scared to speak out against Stonewall because - aside from the wall of silence that has been erected, where anyone who speaks out is viciously cancelled - they are worried that not only will they seem transphobic but homophobic, since Stonewall has exploited the LGB - who it no longer represents in any way - as a vehicle to garner protection for its activities.
As mentioned above, Stonewall is also basically a money-making machine, not only getting millions in taxpayer money and other grants but also making a pretty penny by charging for attendance at its workshops. And attendance at these workshops has almost became mandatory in the public and much of the private sector.