The biggest concern with Bitcoin is currently ease-of-adoption and learning curve. It takes years to really understand Bitcoin, at least for the average person. Even learning how to buy it in the first place can be extremely hard.
This simply isn't true. Bitcoin is easy to understand enough for the layperson to buy it, own it, and spend it.
Using Coinbase (and other exchanges) is incredibly easy. In the time it takes to get verified and approved to use an exchange you can do a little reading and understand how bitcoin works. The only barriers to education are if someone doesn't know English (which most Bitocin resources are likely written in) or doesn't have the intelligence level to understand the basic concepts.
People don't need to know cyrptography or coding to use bitcoin.
And if you're REALLY having trouble understanding bitcoin, check out this
free course on cryptocurrency.