Hair color is changeable. And society hasn't felt that ginger mistreatment has yet become an issue to tackle. There's no major organization lobbying for the rights of redheads (AFAIK). Maybe it's a problem but it sounds like it's isolated and not systemic - apologies if I'm minimizing the suffering of someone who's redheaded and has suffered.
Physical fitness, good hygiene, and dressing well can take most people within a standard deviation of being considered attractive. And in any case "beauty" is far more subjective than race or national origin.
Height is a trickier one but outside of discrimination against people with dwarfism (disability) I'm not sure there's been a pervasive, ongoing, systemic discrimination against tall people or short people. Correct me if I'm wrong about that. I've read occasional research studies about tall people getting more leadership jobs, but I don't know how rigorous those are.
Intelligence - hiring is about capability to do the job, not "intelligence" whatever that means. Employers can use whatever means they want to judge ability with the following conditions:
"...it is unlawful to use a test or selection
procedure that creates adverse impact, unless justified. Adverse impact occurs when there is a
substantially different rate of selection in hiring, promotion, or other employment decisions that
work to the disadvantage of members of a race, sex, or ethnic group."
If an adverse impact occurs the employer can only continue to use that selection procedure
"...if the procedure is job-related and valid
for selecting better workers, and there is no equally effective procedure available that has less
adverse impact."[1]
That second one is (I believe) what makes it legal to put out casting notices asking for actors of a specific sex, age range, or sometimes race. But if an employer can't show that an IQ or aptitude test is job-related, and the test is found to have a disproportionate adverse impact, it can't be used.
Physical fitness, good hygiene, and dressing well can take most people within a standard deviation of being considered attractive. And in any case "beauty" is far more subjective than race or national origin.
Height is a trickier one but outside of discrimination against people with dwarfism (disability) I'm not sure there's been a pervasive, ongoing, systemic discrimination against tall people or short people. Correct me if I'm wrong about that. I've read occasional research studies about tall people getting more leadership jobs, but I don't know how rigorous those are.
Intelligence - hiring is about capability to do the job, not "intelligence" whatever that means. Employers can use whatever means they want to judge ability with the following conditions:
"...it is unlawful to use a test or selection procedure that creates adverse impact, unless justified. Adverse impact occurs when there is a substantially different rate of selection in hiring, promotion, or other employment decisions that work to the disadvantage of members of a race, sex, or ethnic group."
If an adverse impact occurs the employer can only continue to use that selection procedure
"...if the procedure is job-related and valid for selecting better workers, and there is no equally effective procedure available that has less adverse impact."[1]
That second one is (I believe) what makes it legal to put out casting notices asking for actors of a specific sex, age range, or sometimes race. But if an employer can't show that an IQ or aptitude test is job-related, and the test is found to have a disproportionate adverse impact, it can't be used.
1. https://www.onetcenter.org/dl_files/empTestAsse.pdf