Better question... Why are we taking bad pictures and then cropping them all anways... ? The vast majority of real cropping scenarios are actually taking a 4:3 photo and cutting it down to a 3:3 - but that's removing 25% height, not treating crop as a way to zoom in on subjects that were barely captured by a poor photo taken by a poor photographer.
Additionally, how many times does it need to be explained how the limits on smartphone camera technology are not being driven by MP? There's never been a counter argument to the explanations, merely a repetition of the original false statement for which those explanations cost to counter themselves. The OP has not given one single point of evidence nor provided any valid observation to which any logical debate could follow. Here's our conversation so far:
OP: more MP is better
All: actually that's incorrect, here is why
OP: more MP is better
All: well, since you didn't read a word of the last posts we tried to help you with, here's a more detailed explanation
OP: but more MP is better
All: No. Here, try looking at it this way...
OP: but more MP is better and especially better than less MP
All: wtf... Ok one last try...
OP: More MP is better
Let me know if anyone doesn't see the pattern...