It's "rolling your own crypto", not "rolling your own encryption algorithm". That includes using "secure" low-level primitives incorrectly to build an insecure

It's "rolling your own crypto", not "rolling your own encryption algorithm". That includes using "secure" low-level primitives incorrectly to build an insecure higher-level protocol. In this case, using ECB mode has been known for years (decades?) to be a bad move regardless of the underlying encryption algorithm. As the classic article says, if you type the letters A-E-S, you're doing it wrong.