They may seem similar, but the differences are important:

1. Viewing demand - The desire to watch the content
2. Financial demand - The desire for somebody to pay for the content.

The point about the ACC, in addition to having high-quality football, having high-quality men's/women's basketball is a good thing for the viewing demand. If it's on, people will want to watch it. However, I'm not sure that the market for non-football content is all that high yet, to the point where lots of people will pay to see it. There's a reason that football drives the financials, is because there is a large population of people that are willing to pay to watch it. I'm not sure that's there yet for basketball.

Where those difference manifest is that high viewing demand creates profitability for the network in advertising ratings, while high financial demand creates profitability for the network in subscriber fees. While the rights to ACC basketball may be "formidable" in ESPNs eyes, that is due to its ability to drive advertising ratings. I don't think the market is there, yet, for basketball to drive subscriber fees, IM(ns)HO.

However, there is a brighter light at the end of the tunnel. Right now, people are accustomed to basketball games being on somewhere on one of the multitude of existing sports channels, and as those move to more dedicated channels, viewing habits will change. As viewing habits evolve, I think you're going to see more people willing to pony up for baskeball and other non-revs, as people become more accustomed to paying for content that they want to see. As an example, there are some TV shows that I've become accustomed to paying for to stream on Amazon Prime, rather than wait for them to come out on Netflix or Hulu. As this type of transactional nature of media consumption becomes more common (and I think it will, especially when you can watch without commercials), then there's more of a willingness to pay for specific content in general, rather than just watching what's available through subscription services. I think that's a paradigm that will benefit the ACC, with its high-quality non-rev sports content. Eventually, that will drive revenue, but in due time, as viewing habits evolve. Again, this is just IM(ns)HO.

TL;DR: People aren't willing to pay for non-football yet, and that impacts subscriber fees for the ACCN, but long term trends will trend toward better rights fees for the ACC due to high-quality non-football content. IM(ns)HO.