I think the better cryptography lesson is that you should not build your own cryptography system because you will mess up and include a security flaw that will allow the data to be read.
Isn't that the joke? “Anyone is capable of building encryption algorithm that they can’t break” doesn't say that nobody can break it, and it's probably easy for people to assume that "well I can't break it, then it's probably unbreakable" only to discover that in fact it is not unbreakable.
Yes, but it's written more clearly for the people who need to hear the message.
That’s literally the same underlying lesson just stated differently.