As defined in the The Equality Act – age, disability, gender reassignment, race, religion or belief, sex, sexual orientation, marriage and civil partnership and pregnancy and maternity - are all protected characteristics.
The are protected characteristics for a good reason.
The volume of stereotyping and prejudice on here over the last couple of weeks (or months) has been eye watering : People spouting preconceived opinions that are not based on reason or actual experience and the general feelings towards people based solely on their protected characteristics.
If you think it's just a bit of harmless stereotyping, you're wrong. Stereotypes encourage prejudice. Prejudice encourages discrimination.