DLC has a bad sound to it after how many other companies had used it to rip off their customers so I guess people are simply worried when you use the same term and announcing a big change in DLC/patching strategy.
I think this is what most people (Including myself) are worried about, that in the past it has just been a way to rip off customers. I'm not opposed to the concept, just the execution.
To me it sounds like Paradox are essentially implementing a "modular expansion" type of DLC (I'm leaving the sprite packs and the likes out of this, as that's purely cosmetic). Where instead of an expansion after a year, you'd have the features that you might expect from such an expansion released as 4 DLCs spread throughout that year. Allowing you to get just the ones that interest you. Bundling the available DLC together every once in a while for a discount would pretty much be like a classic expansion. A system like this gives flexibility for the customer: For instance that EU3 expansion with the focus on China/Japan. In a DLC system, a patch would've added balance and interface improvements made for that expansion for everyone, but only those who paid for it would have the extra content. The fact that people want those things and pay for them, gives Paradox some money to spend on fixes that will benefit everyone. Win-win. I'd imagine that DLCs also give Paradox a slightly more even revenue stream, which makes their life easier even if the sum total would be the same.
Now, that's a hypothetical example of a DLC system that would make sense to me, providing it's reasonably priced. Hoping to see it, or something similar, at work here with CK2. Having been a loyal Paradox customer for a decade now I have more faith in you than I do most developers so I think it'll turn out decently, but I have been so disappointed in the DLC systems I've seen elsewhere that I still worry.