Can someone make it trading only altcoins?
Follow my lead, you need lots of patience and to avoid losses when trading, just buy low and sell high, all that matters here is timing, orders can get successful in seconds, minutes, hours, days or even months, that's why you need patience
Not only buying low and sell high, learn to study the cryptocurrency market and take the right step in order not to be a victim of dump, as many thousands have been. Many a-times we buy when the price hit the peak, always be right all time to buy from the buy zone than buy from the selling zones. Many have been left with shits because of this.
After a few successful trades people start to think that they are a great trader and can make any coin a gem if they enter the market and then they face the hard truth when they loose what they made in trading. It is always advised to learn along with doing practice, if the trader will forget to do any of these things then the consequences won't be good and as you said he will face the same date as the thousands of people already did.
Trading isn't everyone's cup of tea and everyone should understand their strength and weaknesses and then decide on what earning path they should take in the future.