No doubt knowledge is very much of a key in what ever you do in this life, so Bitcoin is not an exception, but take note that you don't have to have all the knowledge to start your Bitcoin accumulation journey, all you just need is the basic knowledge on how to accumulate it either through DCA accumulating strategy or through lump sum strategy, along the line you can learn more about it and all that are required or needs to be in place to be successful in it.
You correct knowledge is Very much a key in what ever will in this life, and there some investments that requires to have full knowledge about them before you can get started, but in the case of bitcoin investment full knowledge before you can get started is not need, what you just need as a newbie to get started with bitcoin is just basic knowledge about bitcoin, how to buy bitcoin and how to secure your bitcoin you're good to go. bitcoin is not something that you have to wait go get full knowledge before you can get started, because the more you wait to get full knowledge about bitcoin the more you delay your bitcoin investment journey, so getting started with basic knowledge is very important.
Why most Investors are having doubt about starting is because they are not given a proper orientation on Bitcoin and how easy it is to invest in it with your discretionary income, most of them don't know that they can invest in it little by little, , some still think that they must buys a whole Bitcoin at once, but with the basic knowledge about it, that wouldn't be a problem in start or taking the first step.
I also agree with you here, most people have not yet started with bitcoin, because they were not giving the proper orientation on bitcoin and how easy it can be for them to invest in bitcoin with just their discretionary income and not with their whole income. Just as you said many people believe that for them to get started with bitcoin that they need to have a huge amount money to buy bitcoin at once and hold for long, without knowing that they can buy bitcoin fraction by fraction with just their discretionary income consistently using the DCA method till they get to their accumulation target.