Just a minor nit... Apple doesn't really belong on that list. But you're right in general. Cloud storage is a big race to the bottom, and add-ons are going to be what's monetized. I can't see Filecoin or Siacoin having any advantages here.

I don't know how big the Filecoin network is, but it's very telling that they're not sharing this information. I expect that the amount of data stored is not large. Siacoin makes this available but total contracts are currently a bit under 200TB.

For those of you keeping track at home, that's a single medium-size storage appliance.