I think it is a scam. Since months mio. of users are "mining" something with no apparent outcome and a value of still 0? Where are all those Pi? Is there a stats page on how many Pi have been "mined" already?
It shows traits of a Ponzi scheme due to heavy pushing new users to advertise it to other users to get more rewards. Probably the only function is to suck up user addresses and other details.