I have the Sling TV Blue plan in one of the major O&O media markets, and I'm getting very little of any value via TVE within Channels DVR anymore.
I used to get my local NBC affiliate and my local Fox affiliate in my major market city. First the NBC channel access disappeared a long time back, and now more recently, I still show a channel for my Fox affiliate within Channels, but it doesn't actually play any content when I click it.
Within Channels, otherwise, I can still access A&E, History, Lifetime, FS1, Comet, and some misc. news and sports channels that I believe Channels itself provides to subscribers.
Yet for some reason, with the same Sling TV Blue subscription, I still get my local Fox and NBC affiliates via my Stremium / Fitzy subscription, and both play just fine there and always have, along with numerous other regular cable channels via my linked Sling subscription.