If you took that literally it would be impossible to learn cryptography.

Please don't tell people to not roll their own crypto.

Instead tell people to roll whatever they want, but not to use it or allow others to use it for anything serious.

There is a big difference between these two things, and having young people and new people learn about how cryptography works is extremely important going forward.

I too am compelled to repeat the mantra, plz don't roll your own crypto

otpyrc nwo ruoy llor t'nod