The more engagement your content receives, the higher the reach. It's pretty basic.
If your content is sent to 1,000 people an no one likes, shares or comments, it sucks. No one cares. What is the point of showing it to more people?
If your content gets 400 likes, 100 comments and 75 shares, I guarantee that your reach will be much higher.
Stop blaming the system and start sharing content that your fans acutally care about.