Colin. "Powered by" is likely to be a term approved by the management teams of RUK and Skybet, and so you are likely to hear it repeatedly. Once again, I doubt Nick Luck would have chosen the term himself, other than possibly ironically. He, like most of the rest of us, have to spout this management-speak crap at the behest of his bosses from time to time or go off message.
No, I do not think that subscriptions "would have to rise considerably" and did not say so. I think that RUK has done this as a commercial decision which they, as a commercial organisation, are entitled to. If they did not behave in a commercial way they would ultimately, though perhaps not specifically in this instance, pay the price.