My 2c on privacy coins... not worth it unless you trying to play the rotation. What I mean is that there will come a time where people rotate from one sector to another. So eventually privacy coins will get their love, but on a longer time frame, they've always underperformed.
I think they have real use case and totally necessary, but they're relatively terrible investments.
Still a big question mark on the regulatory front. We've seen exchanges delist XMR and Zcash (forgot the ticker?)
Read next
From @w01