How is God of the Bible good, if He is fine with slavery?

If the God of the Bible is good, all-loving, and all-knowing, it seems that the fact that the Bible condones and never prohibits the ownership of humans would negate those attributes.

This God took time to forbid petty and harmless things such as eating shellfish, and wearing mixed clothing, and even killing your disobedient child, but to own someone as a piece of property, where they could be bought, sold, beaten, and slaves for life, and their children born into slavery, it was fine with God, and worse, God knew all the future horrors of millions of slaves that were caught up in this, and much of it from Christian nations.

That doesn't seem to be a good, all-loving, and all-knowing God to me.