I think one of the main problems is ease of entry into crypto some people think they don't have the tech savvy,there is a learning curve but it is not as hard as a lot of people probably believe especially using the big exchanges to start.Then there is all the horror stories of crypto rip offs in all shapes and forms which is also a drawback.Also alot of people only listen too and believe mainstream media and financial institutions and their governments which cant make up their mind about crypto. I think another problem is different generations talk and have different views on cryptocurrencies 20 somethings talk and understand about crypto way more then someone in their 60s. The different generations also have way different financial goals with the younger you are the more risk you are willing to take with your fiat while the boomers may want to preserve their fiat and most do not understand the cryptoverse which is a barrier to their entry.