I disagree with what is being discussed here. There is no such thing as most profitable currency pair.
For trader A, trading EURUSD could be more profitable. For another trader, trading DAX could be most profitable.
The reason I think is that a real professional trader would have spent countless number of hours trading & watching the price movements of his/her active instrument in his/her active session. This is how you find what works for you & what does not.
The profit then comes from scaling up. The higher number of pips does not guarantee higher profits. You can only be making 600 pips on EURUSD in a year, and be extremely profitable, if you know when to size up & when to size down.