Because phones have in my opinion become a privacy nightmare. I think we all got used to it as the new normal because it happend in lots of tiny steps. However, 30 years ago people would have screamed at being constantly and at every step under surveillance, all their contacts recorded at every moment. I simply don't think that modern life with smartphones and internet must be like this. I'd like to have my private life back.

Edit: I recently signed up for LinkedIn and it was outright scary which contacts I got suggested. There were people that don't have my email address nor have I ever been in electronic contact with - I just met them plenty of times in real life. Best explanation is that smartphones correlate location and/or bluetooth MAC addresses. In other words, my phone is spying on me. I don't see any reason to give this information to unknown 3rd parties without my consent.