I highly doubt it'll be priced like that. Why would anyone even buy the game and DLC bundle for $140 (or are you saying $99? even then) if you can buy the Special Edition for $80 that includes ALL DLC and some physical bonus items? So that means that all the DLC + artbook + the special item depending on console ver = $40. So my guess is all the DLC will cost at MAX $30 but I have feeling (and with the backlash they are getting) it may be $20. Which would bring the total cost to $60 (or maybe $70 if it does end up being a $30 dlc pack).
If it turns out to be $60 then this whole thing doesn't really make a difference except it's actually a bit of an advantage for someone who wants a low entry cost or doesn't care about majority of the DLC so they save a little (and the DLC characters won't be in the story mode but I don't think anyone gives a crap about that right now). Anyway, I'm a bit surprised in the way how ArcSys announced this news but I think we should calm down a bit and see more conformations on the pricing.
EDIT: Thinking more about it and looking up Nintendo Switch Storage Pouches being priced at about $10-15 on Amazon, I'm leaning more towards that it'll be $20-25 for all DLC and not up to $30*. But we will see.