It would be better to write 5,000 words and edit them down into a 2,000-word article than to write 500 words and force more in an attempt to build it up.
I really hope universities stop using number of words as a constraint for papers and essays. When in university, most of the time, I used to write what I wanted to, then paraphrase it to bring it to the prescribed number of words. This is the exact opposite of what students should be learning. They should learn to express what they want to, in the most concise and non-bullshit way possible.