Encryption is generally about increasing the amount of time it would take an adversary to access some specific information. The point being that human beings aren't expected to keep information a secret forever, but merely to keep it secret long enough that it doesn't jeopardize the reason it is being kept secret.
So if you are talking about something classified, the human beings who have the burden of keeping their knowledge secret are psychologically tasked with a 24/7 365 job, which costs in terms of "emotional labor", which usually isn't even calculated in the market. They must keep the information secret long enough to protect the operations, and the parties involved, or the national interest, or national security.
A President such as Barack Obama must keep the nations secrets. This means the thoughts inside his head are classified. This means the burden is his to carry, and in some cases his alone. The salary of a President also isn't very high, it's less than $200,00 a year, yet the nature of the job is also under emphasized. Why would anyone ever want to be President of the United States or of any nation?
The conclusion of all of this? No sane person should want a security clearance thinking it's cool to have that kind of responsibility. No sane person should want to have to manage private keys, whether for a Bitcoin wallet, or whatever, because there is a definite psychological cost to doing so and that psychological cost matters.
If we are talking about Bitcoin, that psychological cost could be one of the reasons Bitcoin isn't going to be popular. If we are talking about SAFE Network it's again a situation where the psychological burden for most people is too heavy to be worth whatever privacy benefit they get. It's also something Steemit is going to have to manage which is that the user experience has to take precedent over other aspects. You can make it secure but there comes a point of diminishing returns, where the information being kept secure is no longer worth the burden to the average person.
For this reason, experts and professional companies exist to manage private keys and other exceptionally hard to secure information. In my humble opinion it is important for Steemit to focus on lowering psychological expenses, such as hidden emotional labor. This includes having to remember passwords, dealing with private keys, but also associations with brand buzzwords which have negative connotations like "Bitcoin" when words like "digital currency" can be used instead.