Academics should write for free in mainstream publications. They have a lot of knowledge that is bottled up in obscure academic journals that nobody reads. Theoretically, they know how to write. It’s good for the public to learn about their particular subset of expertise. It’s good for academics to get real world feedback on their studies. Frequent writing helps them hone their writing skills.
Academics should not write for free in mainstream publications, because they are depressing the salaries for people who actually need the money to pay rent and buy food. Their inclusion in the ranks of content providers has flooded the market for wordsmiths.
Not brilliant and consistent two cents. But there you go.