This.
And flip it around:
When women wanted to have for example health support groups about an illness that affected only women, were they permitted to say no to the men who insisted they had to be permitted to enter (and take over) that group because they identified as women? No, the EA was used to force their entry and most of the groups were destroyed. (Because the existence of something about women as a biological entity was unacceptable.)
When women wanted to have lesbian only groups and say this is for women lesbians only, were they allowed? No. Many were destroyed, some went underground to hide from men using the EA to force entry.
One women's rape support group actually ended up moving a meeting to a woman's home to escape the men harassing and wrecking the group, and had the men on the drive way trying to make the police force their right of entry and to prevent the group being allowed to meet without them as it was 'discriminatory'. The EA was the weapon used.
These were all small social groups, not services. Some of them were friendship groups and small clubs.
Single sex groups have to have clear boundaries that they can enforce, and things were pushed to this point by the very same men who are now so upset at one being put down. A bit of generosity on their part and a bit of live and let live, and it might have worked, but they wouldn't have it, and they now don't like the consequences of their own actions. I'm sorry men are upset. I get that it's upsetting to see and hear people upset. But frankly women have to be able to protect themselves from this awful behaviour and it was not 'just a few bad actors' it was everywhere, all the time. The entitlement that's leading to all hell breaking loose at the idea of women having a legal right to say 'no' was exactly the entitlement that wrecked women's services, caused untold harm to women across many groups and organisations without conscience.
Women need this hard line. It's not mean. It's not unkind.
If the WI want to go mixed sex, whatever, fine. It's up to them whether mixed sex or single sex is more important and it's their decision. They just cannot pretend it's single sex when it isn't, and groups and services that choose to be single sex have to BE single sex. And when they do choose to be single sex, they cannot be bullied, brigaded, controlled and destroyed by men on the grounds of being 'discriminatory'.