DLC won't go down in price on consoles because that's where the industry makes most of its money. The costs of AAA games are rising dramatically with every passing year and the entry price for consumers isn't rising along with it, so they have to make up the difference to justify the budgets and production costs somehow. It's probably even more stringent for titles that don't sell as well but have a hardcore, dedicated niche audience that will spend any dollar amount to get all the things for the game.
Also, with the indy scene pricing a lot of highly replayable games at affordable prices that cater to the tastes and needs of those with disposable income, people are choosing to purchase 'new' games over buying DLC for existing games that they've already shelled out considerable cash for.
Although I'm more likely to spend 10 bucks on DLC for a game that cost me 20-30 than I am to buy a season pass for a game that cost me 60.
Personally, I'm at the point where I'd rather just pay $80 for a complete game that has all the content unlockable through community challenges and progression than to keep going on with the $60 'foot in the door' price point and $30 for 'the rest of the game.' I think the industry needs to go in that direction, personally. I think it'll be healthier for the industry as a whole, from conception to development cycle to going gold. It's not a popular opinion because people don't want to spend their ducats, but I care about the enjoyment a game gives me, and if 80 bucks gets me a complete game that I can get legit satisfaction out of, then I'm all for it.