Similarly, under current UK Equalities law jurisprudence, “male critical” beliefs, which deny the existence of men as a separate category from women (“there is only one gender”, in the classic formulation) are *also* protected. Your UK workplace cannot require you to recognize the existence of men.
This is also true. Indeed if the guidance does not protect the philosophical views of disability denialists, it should be altered immediately. “Disability critical” philosophical beliefs are fully protected under current jurisprudence, disabled employees must accommodate those colleagues’ beliefs.