Experts advised to mine only the first 20 coins by capitalization. These are the most famous and understandable projects. Altcoins that seem promising now may be blown away tomorrow.
In the long run, mining BTC is more profitable than mining any altcoin.
Remember that mining is still a medium-term investment, which is unlikely to pay off before 2-3 years. It is worth entering the market only if you are ready to wait and soberly assess the risks.