The problem of mining coins with low difficulty is that these are often new coins that are not even traded on the exchange, or there is a little-known on the exchange, small trading volumes and a low price.
What makes you doubt the profitability of mining.
Not all coins make a profit this way, but you can earn some money quite well.
The same thing could be said about the early days of bitcoin, people were making nothing mining a "worthless" digital currency and look where it ended up. Same thing happens to a lot of new altcoins you just have to be willing to take the risk.