This is a new kind of technology and it needs at least 10 years of development before it's fully functional, it is also difficult for me to digest any need for decentralized cloud storage these days, especially with differences of prices and costs of having internet connection and any computer in different countries, this idea brings nothing to the advantage of individuals trying to keep a system decentralized. people will never be able to compete with the big cloud storage providers because they will always offer cheaper services.
Let me explain why your assumptions are incorrect.
1. First off decentralized Storage is way cheaper than traditional storage, this because farmers already have their computers turned ON, they already paid for the hardware and electricity.
2. One of the biggest limits both on a architectural level and on a price level is bandwidth, datacenters have a limited bandwidth pipe and have to pay allot of money for this bandwidth, while farmers already paid for this bandwidth so there is no extra cost there.
3. Files are encrypted and split into shards, which are uploaded to different hosts on the network. This is called distributed data storage, what are the advantages?, well for one its very hard for a malicious person to retrieve and decrypt the file, secondly, it allows one to sum the bandwidth pipe of all the farmers that hold the shard, which can be staggering (imagine 100x gigabit farmers holding a shard).
4. Decentralized storage will always be able to outcompete centralized storage providers.