LOL.
This action was a stupid action for me, the risk more than a gamble risk. You should know more than 90-95% a cryptocurrency who got listed at coinmarketcap its shitcoin, based on that your chance was not good. Most of the picker from the script will choice a shitcoin, also marketcap can be manipulation by exchange bot.
Yes, because there are more and more exchanges too and even small exchanges are heavily listing coins just by taking some listing fees. I think this idea of buying all coins might work if you are trading on a reputed exchange like poloniex or binance because as per my estimation they will never add any coin just by taking some money, they might take money but they also do their due diligence.
Let us suppose every 1 coin out of 20 pumps hard and gets to 10 times it's value, now you have to agree that this will result is little or no profits because the other 19 coins are most probably going to be dust very soon. yes if you make some research and buy coins then it might be well worth it!