I tend to formulate less flowery, but yes! 
It also depends very much on personal requirements.
Personally, I won’t have to protect multiple heirs against each other, ensuring via some mechanism that the distribution is fair. It’s basically one person (plus my parents?). So, for me, I won’t even deem encryption necessary.
Hiding one copy in our common home and locking one copy in our common bank deposit box should be more than enough. Burglars here with a very high probability look for cash, jewels, and electronics, not for documents that look like crypto currency stuff. (As always: Your mileage may vary.)
(I consider passwords and encryption much more to be against online threats than against threats in the physical world. And a lot of questionable advice comes from strange attack models. “Don’t ever write your password down!”, while it is much more likely that someone on the Internet cracks the password that is easy enough to not write it down than that someone breaks into your home to read it from the Post-It on the monitor. Changes a bit for more public spaces, office, etc. and a lot for high-profile targets.)
And it obviously depends on your loved ones, how detailed the instructions have to be. (In such a fast-developing space, they obviously also have to be adapted from time to time.)
All the smart contract solutions require every heir to already be active not only in crypto in general, but in all ecosystems where you want to bequeath something to them. I would not deem that requirement realistic now or in the near future, not only for me, but for many people.
And since “Friends don’t talk friends into crypto.” (while not the more radical “Friends don’t let friends go into crypto.”) is a principle I hold quite high, I won’t go: “If you want to inherit something from me later, you have to create a Cardano wallet now.”