Do you think black characters like Cyborg are better written by a black person, an Asian character like Totally Awesome Hulk by an Asian writer, and a lesbian Latina character like America written by a lesbian Latina woman? Why or why not? If yes, then ask yourself, “Do I think white characters would be better written by white people?” and follow up with, “So who should write characters like Thanos, who is a purple alien from another planet’s moon?” and finally, “What do I think this says about our society?”)
Read this article from a Marvel executive regarding this: https://www.independent.co.uk/arts-entertainment/books/news/marvel-comic-book-sales-falling-vp-diversity-women-a7662771.html
Are you right-handed or left-handed? How many left-handed people are represented on television or movies? How about in comic books? How many twins are represented in these mediums? How about people with mental health issues, or medical issues, dyslexics, diabetics? Are there any diabetic leading characters on television, even though there are so many people with diabetes in the country? Are left-handed characters written by left-handed people? Or overweight women - are they not sometimes written by slender men?
So let’s think critically about something that many in the media, especially those seeking to make right through diversification, often fail to see: people are multi-faceted, and can’t be defined by simply one attribute. For example, a person being called black simply boils them down to just that one thing; a left-handed person called a lefty, or a person with diabetes being called a diabetic – these simplified labels can be used to segregate people or group them together, even if they have nothing in common. However, a black person, for example, can be a Republican – like Dwayne “The Rock” Johnson; an Asian man can be a breast cancer survivor; and a woman can lead a country – like Mireya Moscoso from Panama or Angela Merkel from Germany. Musicians write songs about all types of people - even about Purple People Eaters - and actors play all types of roles that don't define them as people. Segregation isn't good in real-life practice, and it isn't good in the arts, either.
So writers can write about whatever they feel like writing, ad write characters they want to write, regardless of what popular "social justice" advocates are saying. Remember, without this ability, we wouldn't have characters like Luke Cage or Black Panther - after all, they were written and created by white Jewish men.