This doesn't mean that spot color support is going away.
Other color systems supported by Photoshop's spot color support: ANPA-COLOR, DIC Color Guide, FOCOLTONE, HKS swatches, TRUMATCH.
Which leads me to think that they (Adobe, not Pantone) endlessly tested and researched the maximum they could add to the price if they blamed it on Pantone (who are happy to take the blame because they're so entrenched that it won't affect their business in the slightest.) They did it, and Pantone and Adobe are going to split the proceeds. Or, rather, you're going to "subscribe to a Pantone license" and "subscribe to a Adobe plugin for Pantone management" as a pretense.