The EHRC was most likely the first regulator to be captured in the UK. It has been giving undue weight to trans rights organisations since its inception, because the Equality Act, which the EHRC was created to uphold, restored rights back to the female sex class that the GRA had first removed.
And that is why they have been fighting so hard to abolish the EqA's sex-based exemptions in regard to GRC-holders.
When the GRA was set up in 2004, the Sex Discrimination Act 1975, which provided for a number of female-only legal set asides, was amended so that no male with a GRC could be excluded from them. No one gave any thought to the impact this might have on women at all.
If an employer looking for a female person and using a Genuine Occupational Requirement clause in their ad was confronted with an obvious male, but one in possession of a GRC and therefore legally female, and sought to exclude such a person as being unsuitable for the role, because they clearly hadn't fully transitioned, the newly amended Sex Discrimination Act now stated that the final arbiter on whether the applicant counted as fully transitioned was possession of a GRC. And not an actual transition. Or the needs of the women this employer catered to (IIRC, the example given was a carer).
If you remember that the GRA was purposefully written so as to only make a medical diagnosis but not an actual medical transition mandatory, it's completely incomprehensible that not one person in Blair's government raised any concerns about the impact on women. But they didn't. Not publicly and not in internal communications.
On the contrary, the minister and department responsible for women's equality and rights were cheerleaders of this amendment.
It's the Equality Act which gave us our right back to exclusively female-only legal set asides that could lawfully exclude all males including those who had a GRC.
Trans rights organisations thus did the next best thing - they exercised enormous influence on the statutory guidance the EHRC was writing. This guidance, which is legally binding, duly set out that GRC-holders should be treated "as their acquired gender" at all times (i.e. not be excluded at all), and those who identify as trans but don't have a GRC should normally be treated "as their acquired gender" but could - if justified - be excluded. Which is not at all what the EqA said.
Undoing the consequences of this undue influence will be an enormous undertaking.
Enormous.
But not impossible.