That I cannot know. Shared hosting means that the hosting company is keeping OSC on the same server with some of its other client websites. The client sites don't communicate one with another and are not visibly connected.
When we had a dedicated server (i.e. an entire server for OSC and our other sites) back in time, none of the sites ever attracted enough traffic to slow down the others. It's perfectly possible that in the current setting none of the sites on the shared hosting are enough to slow down the whole on their own either, but that the server is simply overburdened by the sum of everything put together.
