Which of the following broad categories “should” your blog posts fall into?
Micro: like flash fiction, 6 words or fewer.
Short: Perhaps 50 to 200 words.
Medium: Around 500 words.
Long: Between 1000 and 2000.
Extremely long: 5000 words or more.
It partly depends on what you’re hoping to achieve, and partly on how much time you have — and partly on your respect for potential readers’ time! (To convert your word count into reading time, use the Words to Time calculator.)
I wrote quite an extensive article on this subject on 19 November 2020: