Or semantics if you're whatsername Kelley, from Stonewall. They were so sure the law was going to be changed that their guidance put the expected changes in. Lots of institutions, including schools, were caught out with inaccurate wording in their policies.
If it really were just semantics, Stonewall would not have been screaming blue murder when Liz Truss failed to deliver what they wanted.
Gender reassignment and gender isentitiy are not the same. Sex and gender are not the same. Along with GI being listed as a protected characteristic, these flawed policies often replace sex with gender, meaning there is apparently no protection at all for girls, boys, women and men; only for those whose gender identitiy doesn't match their biological sex, hence some schools abandoning single sex toilets which is actually illegal!
What a mess.