if you can go back in time 
) that trading Bitcoin and other alts was very profitable. but for now, it doesnt mean that you can not earn money but more difficult 
In my opinion, it is not matter of going back in time, in fat you can still make a very good amount of money by doing trading of any kind of coin which you can afford to buy especially the coins like that of ETH etc. the fact is you need to have a very good skillset in trading if you are planning for trading and above all, planning of making some good amount of money in the field of trading.) that trading Bitcoin and other alts was very profitable. but for now, it doesnt mean that you can not earn money but more difficult