They’re just an income stream, but as it a future income that was taken as guaranteed for the life of the BT contract, for example, they have value when looking to buy the company hence talked about as an asset. But they aren’t like a machine that you’ve already lurched and it has some residual uses that can be sold.
The key here is what rights the PRL has to rescind future revenues and why that didn’t apply to any club not in the Prem league.