There’s an old adage that you should write what you know. In the nonfiction world, it’s easy to get hooked into providing tons of references. White reading lots of material is great, and certainly plagiarism is bad, very bad, there’s more room than we realize to simply assert what we know.
The content your readers want is uniquely you. Good writing is going to include finding creative new ways to say what many people already know.
My favorite reason for quoting other authors is to pull disparate sources together into one place, to use multiple ideas together to say something new. In other words, if you’re just repeating, don’t bother. But if you can take an idea from over there and mix it with an idea from somewhere else to say something new, then it’s worth quoting.
If you’re addicted to quoting others, maybe it’s time to take a break from reading, so you can spend time asserting yourself more!