It's not necessary fake, but it's near impossible to gain from it especially if done on the phone.
To mine profitably you need a powerful computer and also to buy some Hardware and softwares materials.
I only once used a mining site but it was in rubles. I registered and looked in a few days I had 2-3 rubles and I gave cashout, instant payment. for crypto currencies I honestly don't know if it's legit or fake, I haven't worked with that.
They are so many mining sites for cryptocurrency but most of them aren't real and they end up asking for referral and also to make deposit before getting paid.
There are people who do the mining. It requires so much stuff. There are those mining sites that people invest in them and the site owners use the investment to mine for them. Since it requires so much to mine, those sites always have a high minimum investment.
There are hardly any genuine mining sites and the one that are genuine will require you to invest substantial amount before you can get some reasonable profit.
Crypto mining is not fake depending on the platform or app you are mining from...you can go check review on Google to know the mining site that have been paying for long
Cryptocurrency mining is not fake, in fact it is very legitimate but it's not everyone that can be mining cryptocurrencies because the gadget and tools that are required to mine cryptocurrencies are so enormous and it requires a lot of electricity to be able to mine cryptocurrencies successfully.
A lot of cloud mining programs are fake, a lot of free mining programs are fake, however, if you download mining software and mine on your computer or if you set up your own mining rid, it can be profitable.
Mining of cryptocurrency is never an easy task and you shouldn't expect any simplicity from it. I choose to avoid mining of cryptocurrency and platform that promise to help me do so.