You should learn the both and eventually makes your choice, no crypto enthusiast should limit himself to only a particular aspect, you need some trading knowledge in making investment decisions, both type of trading all have different outcome and requirements. Particularly for a very busy person, long trading should be the best as you do not habw to watch the market all day while short trading requires constant monitoring
Both are good, day trading needs more experience of trading and long term trading can be done easily. I think that day trading is more effective than long term trading because in long term trading you will have to wait for long time and the profit is also not guaranteed. If you analyze the market on daily basis and capable of doing best technical analysis of the market, then no doubt you will earn big money in day trading.