Everyone is on WA and i prefer it too, but I still need their mobile number, so it's more for close friends/family. I communicate with some coworkers i hang out with on Messenger because i haven't bothered to ask them for their number yet. However, i have definitely reduced my FB usage to an absolute minimum, which is mostly a couple of bigger groups I am part of. Instagram is kind of limited as a messenger. At the end of the day, be it FB, WA, IG ...it is still FB your giving your data to ;)