How do you tell people their work is of poor quality?

[Adonai One]

I am editing a Wikipedia article and this older gentleman is restating and adding content in a manner that is often not very readable. A lot of the time he adds just pure filler: additional words and terminology that don't add content or make things easier to read. He tends to just make the article long and more verbose which is the antithesis to what an encyclopedia should be.

My question is this:

I know people make products in all walks of life and have to deal with quality control, especially when you want the best product possible. How do you do it lovingly and without hurting people?