Nobody is saying that trading and at the same time investing in bitcoin is a total waste of time if you can handle both there is no problem with that, but come to think of it if you are trading at the sametime you are investing how can you apply the proper DCA strategy
Actually, If you can trade and invest, that is your personal matter. If you can focus on other things while maintaining DCA while investing on bitcoin, that is entirely your personal matter. But if you cannot maintain DCA while investing in Bitcoin due to focusing on other things, then your investment trend will not be right and you will not be able to control the balance. If you can maintain these, then it is good, but maintaining DCA is the most important thing for investing in Bitcoin, no matter what you do.