Technical my only way to analyse. But I spend a lot of time to learn fundamentals. Why? Coz trading forex you should know all of it sides and understand about different types of market movements.
I trade only FX and I'm going to join with crypto.
I feel many stick to one since this is what they can control or properly oversee, for instance in my case; am into forex trade and crypto trade.
Am comfortable with these and wouldn't want to complicate things more by adding others, at least till the time is right for it.