That’s what Amazon does. If Storj encouraged large datacenters, it would be “Amazon with extra steps”. Might as well stop bothering with node operators and just run your own servers.
For a large company that already has a datacenter - probably not much more than usual.
Current system is made to prevent the types of cheating seen in v2 and to make cheating more difficut in general.
Example 1:
In v2, each node got about equal data, so a valid strategy was to create hundreds of nodes to get as much data as possible. Those nodes were usually slow and not very reliable, but they got (in total) more traffic than a fast and very reliable single node.
However, someone may have a legitimate reason to run multiple nodes - multiple hard drives, spreading the risk and such.
Solution: aggregate all nodes with the same IP address and make them all get about the same data as one (bigger) node. This allows node operators to spread the risk and use multiple devices, but it makes it impossible to get unfair amounts of data.
Example 2:
In v2, a node that declared higher capacity, got more data (there was a very weird reason for it). So, everybody set their nodes to declare 8TB (which was the maximum supported size) to get as much data as possible, then set it to the actual value when the node filled up.
Solution: Distribute data to nodes, that have enough free space, equally.
I can just mod the software to report 10PB to the server.
Storj business model is to provide a service that is cheaper than equivalent service, provided by large datacenters (say, Amazon), but is as reliable (or even more reliable) than those datacenters.
The way to do that is to use home user devices. My internet connection is cheaper than a connection at a datacenter. My labor in looking after my server is cheaper than the same for a company. So, I can provide the same service cheaper. The downside is that my service is less reliable - I do not have as much redundancy as a proper datacenter. That’s where decentralization comes in. Spread the data to lots of nodes and if some of them are inaccessible at the moment - no problem.