People will say "it is not profitable", mostly because them got spoiled from the spring 2017 crypto boom and ROI that was in the matter of months. That being said, actual ROI these days is anywhere from 6-15 months (for the GPU rigs). This depends on what coins you mine and what you do with them. That is still one hell of an investment profit wise. Mine whatever coin gives best results depending on your hardware, dump these coins to btc when they reach nice to-btc-exchange-rate, sell btc once it reaches peaks = profit. Or you could hold the coins if you believe that their price will soar, however only the btc gives some (if any) assurance that it will keep raising in value.
actually for now indeed mining can be profitable and it is also detrimental, as indeed we have no sure thing to see cyrptocurrency where a much more give you an advantage or a guarantee of getting advantage. mining is indeed profitable, but if you don't have a good knowledge of then everything will certainly be detrimental. because mining is always concerned about the analysis, calculation, and innovation.