You might - I certainly don't. I quite like card infusions being at the rate they've been at for as long as the game has existed, thanks. (Also, still disagree about the "reasonable cost" part.)
And if they ever do that, that may matter to me. I see no reason to believe they will though. Instead, they're effectively just making it more expensive by charging for the adventures, and now making those of us who could pass on them out of disinterest in single-player before pay for them anyway by putting new cards into it.
Rarity and dust values mean nothing with cards you're guaranteed to get. They only matter when you need to either get the cards from a pack, where they determine the odds of doing so, or spend dust on them, where they determine the cost of making them. Moreover, all that gold value that you're giving up you wouldn't need to give up if there weren't new cards in this mid-expansion adventure. It just amounts to less cards from the expansion that you can afford to buy over time. And if it goes over well, which it probably will, it will become a regular thing, and thus you'll just have fewer cards from every expansion going forward. If you're like me and weren't ever accumulating all of the cards you'd like to to begin with, that looks pretty darned awful and unreasonable.
I don't. I got at least some enjoyment out of the old style of adventures, where the bosses were more like a puzzle you designed decks around, but Dungeon Run-style gameplay lost my interest very quickly. That's why I've been happily passing on the other new adventures since they started charging for them.
*double-checks* Huh, it is only four wings, rather than the five it's pretty much always been before. Alright, my mistake there, but doesn't really help much to my mind. Twenty eight packs/a month of play time is still absurd to just be told you don't get towards the expansions anymore because they want to add this now.