Cloning an altcoin is trivial and doesn't require knowledge of c/c++ because all the code is already written.
Just tweak some parameters and you have a brand new coin.
True developmnet, specifically mastering it, doesn't require knowledge of any specific language. The language
is just a tool and the job usually determines the appropriate tool to use.
Cryptography, multithreading, networking, gui, distributed processing, etc are the programming skills you need
to master altcoin development.
Truth.
And to truly 'master' it probably takes years.