Please help me by giving me all and any opinions. When we talk about bonsai and a well draining bonsai specific soil mix. We talk about how we want a strong balance of water and oxygen. We also want to avoid root rot which is why we do not use potting soil. My question is simple. if root rot is such an issue and then why is every piece of nursery material planted in potting soil? When we get material from a nursery it is almost always a great looking piece and the pots are completely root bound with ton of healthy roots to work with. If I am looking to grow and thicken my bonsai should I be planting them in nursery pots for a few years with potting soil only?

No, it's not always like that.
Many times the plants come from the ground and are put into pots and nursery soil to be sold in garden shops; many times plants come from greenhouses with watering control and do not adapt as easily to the real world.
But...
Your questions are genuine.
There's nothing wrong with good organic soil if it is aerated and draining; tropicals thrive in organic soil. The secret is the watering schedule, one have to be careful, overwatering and overfeeding could both be a serious issue with organic soil.