It is not bad to take both opportunities. Maybe you are very curious now to your friends approach in his/her trading strategy. Well, very one of us has his own talent, potential and capabilities in every aspect of life. If your friend much preferred using fiat, and have much more profit than yours, then dont be bother by it. Trade with both through crypto currencies and fiat, and move forward. In fact, there is no one that is stopping you to take the both direction. But first, before you enter both of them, you are aware that everything you do, have risks to take and both of them have challenges and obstacles to faced. That is a common part of life, not just in investing or trading but in our everyday doings in life.
Additionally, you must be aware that earnings or profits in trading of fiat currencies are fixed while on the other hand, earning using crypto currencies are not, because we all know how volatile the crypto market is. Both have different perspective in terms of profits.