Op you are right from your point of view. I already invested with a lots of altcoins and most of them turned into scam or dead coin right now. But yeah, many altcoins also gave me profit to. So I can't ingore the whole altcoins sector. Rather it will be wise to select good altcoins which have less possibility to scam and more possibility to generate profit for you. Otherwise you'll be scam by altcoins. So be conscious before investment
If you have gained profit from altcoins and your profit is greater than your loss then its okay you are in profit so forget about the loss. There is also a way to make identification about altcoins nature but for it your experience and knowledge will work better.
There are unlimited coins in crypto market but we have not to choose all of them as there is a huge percentage of scam projects so invest with great care and give time to experimentation.