What did we even know about Bitcoin when we first heard of it? almost nothing until we get curious about it and start learning about its technology and ecosystem. And if both are complicated, do we even need to know how fiat's are made and where they have been made from? no. And that's the same goes for Bitcoin, a user, a holder, or an investor doesn't need to know all of its technicalities because they really are going to be complicated if you're not fond and knowledgeable about it. The basic matters don't have to be complicated at all and it is not requiring a lot of knowledge to be understood. What is important is the value that they have and what it brings to the person who has it. Like for that fiat lover, he'll never understand the importance of bitcoin and it's his own choice to make it look like complicated on his own mind because that's what he's believing and chose to stick with.
Yea, choice is individual decision, so no matter how we try to convince someone once he doesn't Believe in what you are saying there is absolutely nothing you can do about such situations, to individuals who choose fiat over Bitcoin, they feel that Bitcoin is a complicated innovation as the op said the same is applicable to bitcoiners, this is just understanding difference, every Bitcoin enthusiast, more expecially people that has been in the system for a while understands that Bitcoin is a valuable asset that requires a longterm mindset to achieve from the investment but for a novice that has chosen fiat instead of Bitcoin unless he see some evidential proves of what you have achieved so far with Bitcoin, there is nothing you will tell such person that will make him or her to belive that Bitcoin is a good investment unless such individual wants to try the investment based on his interest.
In the aspect of technicalities, I don't think is must for everyone to be involved in that as you said, in whatever investment we choose, the first thing to learn is how things are been done after that, we are good to go may be we can acquire more knowledge when we are fully involved in the said investment.