God definitely has levels of inclusion when it comes to the kingdom. He told the disciples more than He told the crowds because the disciples were hungry to learn. A harsher way of putting it is not casting pearls before swine, so to speak. There are people whose hearts are not open to the truth of God and will reject it, or worse, twist it.
God reveals the deeper truths to those who really want to know. But they have to be ready for it. Jesus said to Nicodemus, If I have told you earthly things and you do not believe, how will you believe if I tell you heavenly things? (John 3:12)
We learn the deeper things of God a little at a time. As we take in one truth, it becomes the foundation for the next. For precept must be upon precept,precept upon precept, Line upon line, line upon line. (Isaiah 28:10)
Do you want to know the deep things of God? Then become a willing student. Meditate on the Word and think about His truth. Ask for more. There is so much that we don’t know, but could know if we only pressed in. It will be like being in the inner circle with Jesus teaching you one on one. How amazing is that!