It's not just a Comcast/Vicaom thing, it's an industry-wide thing. All cable networks are slowly losing subscribers, due to cable/satellite providers getting squeezed by shrinking TV subscriber counts, which is forcing the providers to put a cap on the cost of programming, which, until recently, didn't seem to have a ceiling. So they are dropping channels, or moving them to higher priced tiers, all to avoid raising their price of the most popular programming packages. The cable networks kept charging the providers more for their channels, and forced them to carry all their channels, and the providers passed the costs onto the consumer, who grumbled, but kept paying increasingly more for bloated packages that forced them to subscribe to a multitude of channels that they had no interest in, just to receive the channels that they were interested in.
But now there are alternatives and the cable networks can't force providers to keep paying their accustomed price increases and can't force providers to carry all their channels on the most popular tiers. More people are now "cutting the cord" and just subscribing to streaming services like Netflix, etc., and that is changing the business model of the entire cable television industry. Companies like Viacom and Disney earned windfall profits by forcing providers to carry all of their networks, and substantially increasing the price of their networks to the providers every few years. They are now meeting stiff resistance from the providers, and that is reflected in the falling subscribers counts for Spike and just about every major network, even Disney-owned ESPN. which has fallen from 97.7 million in 2013 to 89.5 million today.